AMC7823IRTARG4 [TI]

ANALOG MONITORING AND CONTROL CIRCUIT;
AMC7823IRTARG4
型号: AMC7823IRTARG4
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

ANALOG MONITORING AND CONTROL CIRCUIT

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AMC7823  
www.ti.com  
SLAS453F APRIL 2005REVISED MARCH 2012  
ANALOG MONITORING AND CONTROL CIRCUIT  
Check for Samples: AMC7823  
1
FEATURES  
APPLICATIONS  
23  
12-Bit ADC (200kSPS):  
Communications Equipment  
Optical Networks  
Eight Analog Inputs  
Input Range 0 to 2 × VREF  
Automatic Test Equipment  
Industrial Control and Monitor  
Medical Equipment  
Programmable VREF, 1.25V or 2.5V  
Eight 12-Bit DACs (2μs Settling Time)  
Four Analog Input Out-of-Range Alarms  
Six General-Purpose Digital I/O  
Internal Bandgap Reference  
DESCRIPTION  
The AMC7823 is a complete analog monitoring and  
control circuit that includes an 8-channel, 12-bit  
analog-to-digital converter (ADC), eight 12-bit digital-  
to-analog converters (DACs), four analog input out-of-  
range alarms, and six GPIOs to monitor analog  
signals and control external devices. Also, the  
AMC7823 has an internal sensor to monitor chip  
temperature, and a precision current source to drive  
remote thermistors, or RTDs, to monitor remote  
temperatures.  
On-Chip Temperature Sensor  
Precision Current Source  
SPI™ Interface, 3V or 5V Logic Compatible  
Single 3V to 5V Supply  
Power-Down Mode/Low Power  
Small Package (QFN-40, 6 x 6 mm)  
Range  
Threshold  
Sync. Load  
(Ext./Internal)  
Analog Input Signal Ground  
Out-of-Range  
Alarm  
DAC 0_OUT  
DAC-0  
CH0  
CH1  
CH2  
CH3  
CH4  
CH5  
CH6  
ADC  
ADC Trigger  
(External / Internal)  
DAC 7_OUT  
DAC-7  
CH7  
CH8  
Channel Select  
TEMP  
On-Chip  
Temperature  
Sensor  
Ext. Ref _ IN  
Reference  
Precision_Current  
Current_Setting Resistor  
Serial-Parallel Shift Reg  
SPI Interface  
Registers and  
Control Logic  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
2
3
SPI is a trademark of Motorola, Inc.  
All other trademarks are the property of their respective owners.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2005–2012, Texas Instruments Incorporated  
AMC7823  
SLAS453F APRIL 2005REVISED MARCH 2012  
www.ti.com  
DESCRIPTION (CONTINUED)  
The AMC7823 has an internal programmable reference (+2.5V or +1.25V), and an SPI serial interface. An  
external reference can be used as well. Typical power dissipation is 100mW. The analog input range is 0V to  
+5V, and the analog output range is 0V to +2.5V or 0V to +5V. The AMC7823 is ideal for multichannel  
applications where low power and small size are critical. The AMC7823 is available in a 40-lead QFN package  
and is fully specified over the –40°C to +85°C temperature range.  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with  
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more  
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.  
PACKAGE/ORDERING INFORMATION(1)  
PACKAGE-  
LEAD  
(DESIGNATOR)  
SPECIFIED  
TEMPERATURE  
RANGE  
PACKAGE  
MARKING  
ORDERING  
NUMBER  
TRANSPORT  
MEDIA, QUANTITY  
PRODUCT  
AMC7823  
AMC7823  
AMC7823IRTAT  
AMC7823IRTAR  
Tape and Reel, 250  
Tape and Reel, 2000  
AMC7823  
QFN-40 (RTA)  
–40°C to +85°C  
(1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI  
web site at www.ti.com.  
ABSOLUTE MAXIMUM RATINGS(1)  
Over operating free-air temperature range, unless otherwise noted.  
PARAMETER  
AMC7823  
–0.3 to +6  
–0.3 to BVDD + 0.3  
–0.3 to AVDD + 0.3  
±20  
UNIT  
V
AVDD, DVDD, BVDD to GND  
Digital input voltage to GND  
Analog input voltage to GND  
Input current, continuous  
Input current, momentary  
Operating temperature range  
Storage temperature range  
V
V
mA  
mA  
°C  
±100  
–40 to +105  
–65 to +150  
+150  
°C  
Junction temperature range (TJ max)  
Power dissipation  
°C  
(TJ max – TA) / θJA  
15  
W
θJC  
θJA  
°C/W  
°C/W  
Thermal impedance  
60  
(1) Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to absolute  
maximum conditions for extended periods may affect device reliability.  
2
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Copyright © 2005–2012, Texas Instruments Incorporated  
Product Folder Link(s): AMC7823  
 
AMC7823  
www.ti.com  
SLAS453F APRIL 2005REVISED MARCH 2012  
ELECTRICAL CHARACTERISTICS: +5V  
At –40°C to +85°C, AVDD = 5V, DVDD = 5V, BVDD = 3V to 5V, using external 2.5V reference, unless otherwise noted.  
AMC7823  
PARAMETER  
ADC ANALOG INPUTS  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Input voltage range  
Input impedance  
Input capacitance  
Input leakage current  
ANALOG-TO-DIGITAL CONVERTER  
Resolution  
0
2 × VREF  
V
5
15  
±1  
MΩ  
pF  
μA  
12  
Bits  
Bits  
LSB(1)  
No missing codes  
Integral linearity  
Differential linearity  
Offset error  
12  
–1.25  
–1  
+1.25  
+1.25  
±2  
LSB  
LSB  
Offset error drift  
Offset error match  
Gain error  
±4  
ppmFS/°C  
LSB  
0.5  
1
±6  
1
LSB  
Gain error match  
Noise  
0.3  
70  
LSB  
μVRMS  
dB  
Power-supply rejection  
Sample rate(2)  
AVDD = 5V ±5%  
70  
200  
45  
kHz  
Total conversion time  
Scan Channels 0 through 7  
μs  
Total conversion time including temperature Scan Channels 0 through 8  
56  
μs  
Channel-to-channel isolation  
DIGITAL-TO-ANALOG CONVERTER(3)  
Output voltage range  
Output current  
VIN = 5VPP at 10kHz  
0.5  
LSB  
Programmable  
0
2 × VREF  
V
mA  
Refer to Typical Characteristics  
±1  
±2  
Resolution  
Integral linearity(4)  
12  
±8  
Bits  
LSB  
Monotonicity  
12  
Bits  
Differential linearity  
±0.2  
±0.5  
±1  
±1  
±5  
LSB  
Output range = 0 to VREF  
mV  
Offset error  
Output range = 0 to 2 × VREF  
±10  
mV  
Offset error drift  
Gain error  
±4  
ppmFS/°C  
%FS  
Output range = 0 to 2 × VREF  
±0.3  
±1.0  
Step between code 0x400 to 0xC00,  
to ±1LSB  
Settling time  
2
μs  
Code change glitch  
Overshoot  
1LSB change, in worst case  
20  
200  
nV-s  
mV  
Step between code 0x400 to 0xC00  
Step between code 0x400 to 0xC00  
Crosstalk  
< 0.5  
LSB  
Sine wave (1kHz, 5VPP) generated by DAC,  
sampling at 400kSPS, RL = 10k,  
CL = 100pF  
Signal-to-noise ratio  
74  
dB  
Output buffer gain = 2  
Output buffer gain = 1  
60  
30  
nV/Hz  
nV/Hz  
Output noise voltage density  
(1) LSB means least significant bit.  
(2) Single-channel conversion only. Does not include control logic delay associated with ADC operation, such as from the trigger signal to  
the start of conversion.  
(3) DAC is tested with load of 25kin parallel with 100pF to ground.  
(4) Measured from code 0x008 to 0xFFF.  
Copyright © 2005–2012, Texas Instruments Incorporated  
Submit Documentation Feedback  
3
Product Folder Link(s): AMC7823  
AMC7823  
SLAS453F APRIL 2005REVISED MARCH 2012  
www.ti.com  
ELECTRICAL CHARACTERISTICS: +5V (continued)  
At –40°C to +85°C, AVDD = 5V, DVDD = 5V, BVDD = 3V to 5V, using external 2.5V reference, unless otherwise noted.  
AMC7823  
PARAMETER  
PRECISION CURRENT SOURCE  
Output current range  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
0.01  
99.5  
10  
mA  
μA  
Output current accuracy  
Output current drift  
Iout = 100μA  
Iout = 100μA  
Iout = 100μA  
100.0  
40  
100.5  
ppm/°C  
MΩ  
Output impedance  
100  
Compliance voltage of pin  
PRECISION_I_OUTPUT  
Iout = 10mA  
3
4.25  
60  
V
Power-supply rejection ratio  
dB  
VOLTAGE REFERENCE (VREF  
Internal reference voltage(5)  
Internal reference drift  
)
At +25°C  
2.495  
2.50  
±15  
2.505  
2.55  
V
–40°C to +85°C  
ppm/°C  
Output impedance of pin EXT_REF_IN  
as internal reference output  
10  
kΩ  
Short-circuit current  
250  
μA  
V
External reference voltage  
1.20  
–40  
Internal reference selected  
10  
1
kΩ  
MΩ  
pF  
External reference input resistance  
Internal reference de-selected  
External reference input capacitance  
TEMPERATURE SENSOR  
Temperature range  
5
+85  
°C  
°C  
°C  
°C  
°C  
VREF = 2.5V  
VREF = 1.25V  
VREF = 2.5V  
VREF = 1.25V  
+3.2  
+1.6  
±4  
Resolution  
Accuracy  
±2.0  
LEVEL OF PIN GALR AND DAV  
IOH = 0.7mA  
2.4  
0
BVDD  
0.4  
V
V
IOL = 180μA  
DIGITAL INPUT/OUTPUT, EXCEPT PIN GALR AND DAV  
VIH  
VIL  
BVDD = 5V, IIH = 5μA  
3.5  
0
BVDD + 0.3  
0.8  
V
V
BVDD = 5V, IIL = –5μA  
BVDD = 5V, IOH = –3mA  
BVDD = 5V, IOL = 3mA  
BVDD = 3V, IIH = 5μA  
BVDD = 3V, IIL = –5μA  
BVDD = 3V, IOH = –3mA  
BVDD = 3V, IOL = 3mA  
Logic level  
Logic level  
VOH  
VOL  
VIH  
VIL  
4
BVDD  
0.4  
V
0
V
2.1  
0
BVDD + 0.3  
0.6  
V
V
VOH  
VOL  
2.4  
0
BVDD  
0.4  
V
V
Input capacitance  
5
pF  
(5) Bit GREF in AMC Status/Configuration Register determines the internal reference voltage. The internal VREF = 2.5V when GREF = 1,  
and the internal VREF = 1.25V when GREF = 0 (see AMC Status/Configuration Register for details).  
4
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Copyright © 2005–2012, Texas Instruments Incorporated  
Product Folder Link(s): AMC7823  
 
 
 
AMC7823  
www.ti.com  
SLAS453F APRIL 2005REVISED MARCH 2012  
ELECTRICAL CHARACTERISTICS: +5V (continued)  
At –40°C to +85°C, AVDD = 5V, DVDD = 5V, BVDD = 3V to 5V, using external 2.5V reference, unless otherwise noted.  
AMC7823  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
POWER-SUPPLY REQUIREMENTS  
AVDD  
2.7  
2.7  
2.7  
5
5.5  
5.5  
5.5  
V
V
V
Power-  
supply  
voltage  
(6)  
DVDD  
BVDD  
(7)  
In normal operation,  
precision current source = 0, no DAC load  
15  
20  
Quiescent current of AVDD  
mA  
All power-down  
1
0.3  
Quiescent current of DVDD  
Quiescent current of BVDD  
Power dissipation  
mA  
mA  
mW  
0.1  
100  
TEMPERATURE RANGE  
Specified performance  
Storage  
–40  
–65  
+85  
°C  
°C  
+150  
(6) DVDD must equal AVDD  
.
(7) BVDD must not be greater than AVDD or DVDD  
.
Copyright © 2005–2012, Texas Instruments Incorporated  
Submit Documentation Feedback  
5
Product Folder Link(s): AMC7823  
AMC7823  
SLAS453F APRIL 2005REVISED MARCH 2012  
www.ti.com  
ELECTRICAL CHARACTERISTICS: +3V  
At –40°C to +85°C, AVDD, DVDD, BVDD = 3V, using external 1.25V reference, unless otherwise noted.  
AMC7823  
PARAMETER  
ADC ANALOG INPUTS  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Input voltage range  
Input impedance  
Input capacitance  
Input leakage current  
ANALOG-TO-DIGITAL CONVERTER  
Resolution  
0
2 × VREF  
V
5
15  
±1  
MΩ  
pF  
μA  
12  
Bits  
Bits  
LSB(1)  
No missing codes  
Integral linearity  
Differential linearity  
Offset error  
12  
–1.25  
–1  
+1.25  
+1.25  
±3  
LSB  
LSB  
Offset error drift  
Offset error match  
Gain error  
±4  
ppmFS/°C  
LSB  
0.5  
1
±12  
1.5  
LSB  
Gain error match  
Noise  
0.3  
70  
LSB  
μVRMS  
dB  
Power-supply rejection  
Sample rate(2)  
AVDD = 3V ±5%  
70  
200  
47  
kHz  
Total conversion time  
Scan Channels 0 through 7  
μs  
Total conversion time including temperature Scan Channels 0 through 8  
58  
μs  
Channel-to-channel isolation  
DIGITAL-TO-ANALOG CONVERTER(3)  
Output voltage range  
Output current  
VIN = 2.5VPP at 10kHz  
0.5  
LSB  
Programmable  
0
2 × VREF  
V
mA  
Refer to Typical Characteristics  
±1  
±2  
Resolution  
Integral linearity(4)  
12  
±8  
Bits  
LSB  
Monotonicity  
12  
Bits  
Differential linearity  
±0.2  
±0.5  
±1  
±1  
±5  
LSB  
Output range = 0 to VREF  
mV  
Offset error  
Output range = 0 to 2 x VREF  
±10  
mV  
Offset error drift  
Gain error  
±4  
ppmFS/°C  
%FS  
Output range = 0 to 2 x VREF  
±0.2  
±1.0  
Step between code 0x400 to 0xC00,  
to ±1LSB  
Settling time  
2
μs  
Code change glitch  
Overshoot  
1LSB change, in worst case  
20  
200  
nV-s  
mV  
Step between code 0x400 to 0xC00  
Step between code 0x400 to 0xC00  
Crosstalk  
<0.5  
LSB  
Sine wave (1kHz, 5VPP) generated by DAC,  
sampling at 400kSPS, RL = 10k,  
CL = 100pF  
Signal-to-noise ratio  
74  
dB  
Output buffer gain = 2  
Output buffer gain = 1  
60  
30  
nV/Hz  
nV/Hz  
Output noise voltage density  
(1) LSB means least significant bit.  
(2) Single-channel conversion only. Does not include control logic delay associated with ADC operation, such as from the trigger signal to  
the start of conversion.  
(3) DAC is tested with load of 25kin parallel with 100pF to ground.  
(4) Measured from code 0x008 to 0xFFF.  
6
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Copyright © 2005–2012, Texas Instruments Incorporated  
Product Folder Link(s): AMC7823  
AMC7823  
www.ti.com  
SLAS453F APRIL 2005REVISED MARCH 2012  
ELECTRICAL CHARACTERISTICS: +3V (continued)  
At –40°C to +85°C, AVDD, DVDD, BVDD = 3V, using external 1.25V reference, unless otherwise noted.  
AMC7823  
PARAMETER  
PRECISION CURRENT SOURCE  
Output current range  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
0.01  
99.5  
10  
mA  
μA  
Output current accuracy  
Output current drift  
Iout = 100μA  
Iout = 100μA  
Iout = 100μA  
100.0  
40  
100.5  
ppm/°C  
MΩ  
Output impedance  
100  
Compliance voltage of pin  
PRECISION_I_OUTPUT  
AVDD = 2.7V, Iout = 10mA  
1.9  
2
V
Power-supply rejection ratio  
60  
dB  
VOLTAGE REFERENCE (VREF  
Internal reference voltage(5)  
Internal reference drift  
)
At +25°C  
1.247  
1.25  
±20  
1.253  
V
–40°C to +85°C  
ppm/°C  
Output impedance of pin EXT_REF_IN  
as internal reference output  
10  
kΩ  
Short-circuit current  
125  
μA  
V
External reference voltage  
External reference input resistance  
External reference input capacitance  
TEMPERATURE SENSOR  
Temperature range  
1.20  
–40  
1.28  
85  
10  
5
kΩ  
pF  
°C  
°C  
°C  
Resolution  
1.6  
Accuracy  
±2.0  
LEVEL OF PIN GALR AND DAV  
IOH = 0.3mA  
2.4  
0
DVDD  
0.4  
V
V
IOL = 125μA  
DIGITAL INPUT/OUTPUT, EXCEPT PIN GALR AND DAV  
VIH  
VIL  
IIH = 5μA  
2.1  
0
BVDD + 0.3  
0.6  
V
V
IIL = –5μA  
IOH = –3mA  
IOL = 3mA  
Logic level  
VOH  
VOL  
2.4  
0
BVDD  
0.4  
V
V
Input capacitance  
5
3
pF  
POWER SUPPLY REQUIREMENTS  
AVDD  
2.70  
2.70  
2.70  
3.3  
3.3  
3.3  
15  
V
V
Power-  
supply  
voltage  
DVDD  
BVDD  
(6)  
V
In normal operation  
All power-down  
10  
1
mA  
mA  
mA  
mA  
mW  
Quiescent current of AVDD  
Quiescent current of DVDD  
Quiescent current of BVDD  
Power dissipation  
0.3  
0.1  
60  
TEMPERATURE RANGE  
Specified performance  
Storage  
–40  
–65  
+85  
°C  
°C  
+150  
(5) Bit GREF in AMC Status/Configuration Register determines the internal reference voltage. GREF must be cleared when AVDD is less  
than 5V and the internal reference is selected (see AMC Status/Configuration Register for details).  
(6) BVDD must be not greater than AVDD or DVDD  
.
Copyright © 2005–2012, Texas Instruments Incorporated  
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Product Folder Link(s): AMC7823  
AMC7823  
SLAS453F APRIL 2005REVISED MARCH 2012  
www.ti.com  
PIN CONFIGURATION  
RTA PACKAGE  
QFN-40  
(TOP VIEW)  
30 29 28 27 26 25 24 23 22 21  
CH7  
CH6  
CH5  
CH4  
AVDD  
AGND  
CH3  
CH2  
CH1  
CH0  
CONVERT  
SCLK  
31  
20  
19  
18  
17  
16  
15  
14  
13  
12  
11  
32  
33  
34  
35  
36  
37  
38  
39  
MOSI  
MISO  
SS  
AMC7823  
Thermal Pad(1)  
BVDD  
DVDD  
DGND  
GPIO−4  
GPIO−5  
40  
1
2
3
4
5
6
7
8
9
10  
NOTE: (1) Thermal pad must be connected to the analog ground; refer to the package drawing for more information.  
TERMINAL FUNCTIONS  
TERMINAL  
DESCRIPTION  
NAME  
NO.  
Global analog input out-of-range alarm. GALR pin goes low (active) when one (or more) of the first  
four accessed analog inputs is out of preset range.  
1
GALR  
Data available indicator. In the direct mode, DAV pin goes low (active) when the conversion finishes.  
In Auto-mode, a 2μs pulse (active low) appears on this pin when conversion cycle finishes (see ADC  
Operation and Registers for details). DAV stays high when deactivated.  
2
DAV  
External DAC synchronous load trigger. DACs that have external synchronous load selected are  
updated simultaneously by the rising edge of ELDAC.  
3
4
ELDAC  
The resistor connected from analog supply to this pin sets the current output from the pin  
PRECISION_I_OUTPUT.  
ISET_RESISTOR  
5
6
7
8
9
PRECISION_I_OUTPUT  
DAC 0_OUT  
Current output to drive a thermistor.  
Output of DAC 0  
DAC 1_OUT  
Output of DAC 1  
DAC 2_OUT  
Output of DAC 2  
DAC 3_OUT  
Output of DAC 3  
Analog input signal ground. This pin must connect to the ground of the analog input source in order  
to minimize digital noise.  
10  
SGND  
8
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Copyright © 2005–2012, Texas Instruments Incorporated  
Product Folder Link(s): AMC7823  
AMC7823  
www.ti.com  
SLAS453F APRIL 2005REVISED MARCH 2012  
TERMINAL FUNCTIONS (continued)  
TERMINAL  
NAME  
DESCRIPTION  
NO.  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
CH0  
CH1  
Analog input channel 0  
Analog input channel 1  
Analog input channel 2  
Analog input channel 3  
Analog ground  
CH2  
CH3  
AGND  
AVDD  
CH4  
Analog power supply, +3V to +5V. Must be the same value as DVDD.  
Analog input channel 4  
CH5  
Analog input channel 5  
CH6  
Analog input channel 6  
CH7  
Analog input channel 7  
When external reference connects here, the internal reference is overridden. When internal reference  
is selected, this pin works as output of the internal reference (with 10koutput impedance). See  
Reference section for details.  
21  
EXT_REF_IN  
22  
23  
24  
25  
26  
27  
28  
29  
30  
DAC 4_OUT  
DAC 5_OUT  
DAC 6_OUT  
DAC 7_OUT  
RESET  
Output of DAC 4  
Output of DAC 5  
Output of DAC 6  
Output of DAC 7  
Reset input. Logic low on this pin causes the part to perform hardware reset.  
Multiple function I/O pin. Works as digital I/O or ALR pin of the first analog input.  
Multiple function I/O pin. Works as digital I/O or ALR pin of the second analog input.  
Multiple function I/O pin. Works as digital I/O or ALR pin of the third analog input.  
Multiple function I/O pin. Works as digital I/O or ALR pin of the fourth analog input.  
GPIO-0/ALR0  
GPIO-1/ALR1  
GPIO-2/ALR2  
GPIO-3/ALR3  
External conversion trigger. The rising edge starts sampling and conversion of the ADC when  
external trigger mode is selected.  
31  
CONVERT  
32  
33  
34  
SCLK  
MOSI  
MISO  
Serial clock input  
Master out, slave in. Digital data input for the serial interface  
Master in, slave out. Digital data output for the serial interface  
Slave select input (active low). Data is not clocked into MOSI unless SS is low. When SS is high,  
MISO is in high-impedance status.  
35  
SS  
36  
37  
38  
39  
40  
BVDD  
Interface power supply. Connects to 3V for 3V logic; connects to 5V for 5V logic.  
Digital power supply (+3V to +5V). Must be the same value as AVDD.  
Digital ground  
DVDD  
DGND  
GPIO-4  
GPIO-5  
General-purpose digital I/O pin  
General-purpose digital I/O pin  
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TIMING CHARACTERISTICS: +5V  
At –40°C to +85°C, AVDD = DVDD = 5V, and BVDD = 5V, unless otherwise noted.  
PARAMETER  
MIN  
42  
21  
21  
21  
42  
0
MAX  
UNIT  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
tsck  
SCLK period  
twsck  
SCLK high or low time  
SS enable lead time  
SS enable lag time  
Sequential transfer delay  
Data setup time  
tLead  
tLag  
ttd  
tsu  
thi  
Data hold time (inputs)  
Data hold time (outputs)  
Slave access time  
Slave MISO disable time  
Data valid  
21  
0
tho  
tA  
21  
21  
10  
30  
30  
tdis  
tv  
tr  
Rise time  
tf  
Fall time  
tWLDAC  
tCONVERT  
ELDAC width  
210  
210  
CONVERT width  
TIMING CHARACTERISTICS: +3V  
At –40°C to +85°C, AVDD = DVDD = 3V, and BVDD = 3V, unless otherwise noted.(1)  
PARAMETER  
MIN  
84  
42  
42  
42  
84  
0
MAX  
UNIT  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
tsck  
SCLK period  
twsck  
SCLK high or low time  
SS enable lead time  
SS enable lag time  
Sequential transfer delay  
Data setup time  
tLead  
tLag  
ttd  
tsu  
thi  
Data hold time (inputs)  
Data hold time (outputs)  
Slave access time  
Slave MISO disable time  
Data valid  
42  
0
tho  
tA  
42  
42  
10  
30  
30  
tdis  
tv  
tr  
Rise time  
tf  
Fall time  
tWLDAC  
tCONVERT  
ELDAC width  
420  
420  
CONVERT width  
(1) For AVDD = DVDD = 5V, BVDD = 3V, refer to the specification shown in this table.  
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SLAS453F APRIL 2005REVISED MARCH 2012  
t
Lag  
SS  
t
td  
t
SCK  
t
wsck  
t
t
Lead  
t
r
f
SCLK  
t
wsck  
t
su  
t
hi  
Command  
BIT 15 (MSB)  
Command  
BIT 14 ...1  
Command  
BIT 0 (LSB)  
MOSI  
MISO  
Don’t Care  
Don’t Care  
READ COMMAND FROM THE HOST  
t
A
t
t
t
dis  
v
ho  
Hi−Z  
HiZ  
DATA OUT  
BIT 15 (MSB)  
DATA OUT  
BIT 14  
DATA OUT  
BIT 13 ... 1  
DATA OUT  
BIT 0 (LSB)  
MISO is in Hi-Z Before Finishing Address Decoding  
DATA READ FROM AMC7823 REGISTERS  
Note: If SS is High, MISO is in Hi-z  
Figure 1. Read Operation (SPI)  
t
Lag  
SS  
t
td  
t
sck  
t
Lead  
t
f
t
r
t
wsck  
SCLK  
MOSI  
t
wsck  
t
t
hi  
su  
Data In  
Bit 14 . . 1  
Command  
Bit 15 (MSB)  
Command  
Bit 14 . . 1  
Command  
Bit 0 (LSB)  
Data In  
Bit 15 (MSB)  
Data In  
Bit 0 (LSB)  
Don’t Care  
Don’t Care  
WRITE COMMAND FROM HOST  
DATA WRITTEN INTO AMC7823 REGISTERS  
Hi−Z  
MISO  
ELDAC  
tWLDAC  
tCONVERT  
CONVERT  
Figure 2. Write Operation (SPI)  
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TYPICAL CHARACTERISTICS: ANALOG-TO-DIGITAL CONVERTER (ADC)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
LINEARITY ERROR vs CODE  
LINEARITY ERROR vs CODE  
(–40°C, AVDD = 5V, VREF = 2.5V)  
(–40°C, AVDD = 2.7V, VREF = 1.25V)  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
0
0
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
0
0
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
Figure 3.  
Figure 4.  
LINEARITY ERROR vs CODE  
(+25°C, AVDD = 5V, VREF = 2.5V)  
LINEARITY ERROR vs CODE  
(+25°C, AVDD = 2.7V, VREF = 1.25V)  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
512 1024 1536 2048 2560 3072 3584 4096  
Code  
512 1024 1536 2048 2560 3072 3584 4096  
Code  
Figure 5.  
Figure 6.  
LINEARITY ERROR vs CODE  
(+85°C, AVDD = 5V, VREF = 2.5V)  
LINEARITY ERROR vs CODE  
(+85°C, AVDD = 2.7V, VREF = 1.25V)  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
512 1024 1536 2048 2560 3072 3584 4096  
Code  
512 1024 1536 2048 2560 3072 3584 4096  
Code  
Figure 7.  
Figure 8.  
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TYPICAL CHARACTERISTICS: ANALOG-TO-DIGITAL CONVERTER (ADC) (continued)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
OFFSET ERROR AND OFFSET ERROR MATCH  
vs TEMPERATURE  
GAIN ERROR AND GAIN ERROR MATCH  
vs TEMPERATURE  
1.0  
0.8  
0.6  
0.4  
0.2  
0.0  
0.2  
0.4  
0.6  
0.8  
1.0  
4.0  
3.0  
2.0  
1.0  
0
AVDD = 5V  
VREF = 2.5V  
AVDD = 5V  
VREF = 2.5V  
Gain Error  
Offset Error  
Offset Error Match  
Gain Error Match  
1.0  
2.0  
3.0  
4.0  
20  
60  
40  
0
20  
40  
60  
80  
100  
100  
5.5  
20  
60  
40  
0
20  
40  
60  
80  
100  
_
Temperature ( C)  
_
Temperature ( C)  
Figure 9.  
Figure 10.  
OFFSET ERROR AND OFFSET ERROR MATCH  
vs TEMPERATURE  
GAIN ERROR AND GAIN ERROR MATCH  
vs TEMPERATURE  
1.0  
0.8  
0.6  
0.4  
0.2  
0
4.0  
3.0  
2.0  
1.0  
0
AVDD = 2.7V  
VREF = 1.25V  
AVDD = 2.7V  
VREF = 1.25V  
Gain Error  
Offset Error Match  
Offset Error  
Gain Error Match  
0.2  
0.4  
0.6  
0.8  
1.0  
1.0  
2.0  
3.0  
4.0  
25  
50  
0
25  
50  
75  
50  
25  
0
25  
50  
75  
100  
_
Temperature ( C)  
_
Temperature ( C)  
Figure 11.  
Figure 12.  
GAIN AND OFFSET ERROR  
vs 5V SUPPLY  
GAIN AND OFFSET ERROR MATCH  
vs 5V SUPPLY  
4.0  
3.0  
2.0  
1.0  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
VREF = 2.5V  
VREF = 2.5V  
Offset  
Gain  
1.0  
2.0  
3.0  
4.0  
Gain Match  
Offset Match  
4.5  
4.75  
5.0  
5.25  
4.5  
4.75  
5.0  
5.25  
5.5  
5V Supply Voltage (V)  
5V Supply Voltage (V)  
Figure 13.  
Figure 14.  
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TYPICAL CHARACTERISTICS: ANALOG-TO-DIGITAL CONVERTER (ADC) (continued)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
GAIN AND OFFSET ERROR  
GAIN AND OFFSET ERROR MATCH  
vs  
vs  
3V SUPPLY  
3V SUPPLY  
12.0  
8.0  
4.0  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
VREF = 1.25V  
VREF = 1.25V  
Gain Match  
Gain  
Offset  
Offset Match  
4.0  
8.0  
12.0  
2.7  
2.85  
3.0  
3.15  
3.3  
2.7  
2.85  
3.0  
3.15  
3.3  
3V Supply Voltage (V)  
3V Supply Voltage (V)  
Figure 15.  
Figure 16.  
INTERNAL REFERENCES  
vs AVDD VOLTAGE  
2.5V AND 1.25V INTERNAL REFERENCES  
vs TEMPERATURE  
2.5004  
2.5002  
2.5000  
2.4998  
2.4996  
2.4994  
2.4992  
2.4990  
1.2504  
1.2502  
1.2500  
1.2498  
1.2496  
1.2494  
1.2492  
1.2490  
1.0  
0.5  
0
AVDD = 5V or 3V  
0.5  
1.0  
1.5  
2.0  
2.5  
3.0  
3.5  
4.0  
2.5VREF  
1.25VREF  
2.5VREF  
1.25VREF  
2.5  
3.0  
3.5  
4.0  
4.5  
5.0  
5.5  
20  
60  
40  
0
20  
40  
60  
80  
100  
AVDD Voltage (V)  
_
Temperature ( C)  
Figure 17.  
Figure 18.  
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TYPICAL CHARACTERISTICS: ANALOG-TO-DIGITAL CONVERTER (ADC) (continued)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
INTERNAL 2.5V REFERENCE  
(AVDD = 5V)  
INTERNAL 1.25V REFERENCE  
(AVDD = 2.7V)  
25  
20  
15  
10  
5
60  
50  
40  
30  
20  
10  
0
0
1.247 1.248 1.249 1.250 1.251 1.252 1.253  
Histogram Bins (V)  
Histogram Bins (V)  
Figure 19.  
Figure 20.  
TYPICAL CHARACTERISTICS: DIGITAL-TO-ANALOG CONVERTER (DAC)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
LINEARITY ERROR vs CODE  
LINEARITY ERROR vs CODE  
(–40°C, AVDD = 5V, VREF = 2.5V, GAIN = 1)  
(–40°C, AVDD = 2.7V, VREF = 1.25V, GAIN = 1)  
8.0  
6.0  
4.0  
2.0  
0
8.0  
6.0  
4.0  
2.0  
0
2.0  
4.0  
6.0  
8.0  
2.0  
4.0  
6.0  
8.0  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
Figure 21.  
Figure 22.  
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TYPICAL CHARACTERISTICS: DIGITAL-TO-ANALOG CONVERTER (DAC) (continued)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
LINEARITY ERROR vs CODE  
LINEARITY ERROR vs CODE  
(+25°C, AVDD = 5V, VREF = 2.5V, GAIN = 1)  
(+25°C, AVDD = 2.7V, VREF = 1.25V, GAIN = 1)  
8.0  
6.0  
4.0  
2.0  
0
8.0  
6.0  
4.0  
2.0  
0
2.0  
4.0  
6.0  
8.0  
2.0  
4.0  
6.0  
8.0  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
Figure 23.  
Figure 24.  
LINEARITY ERROR vs CODE  
LINEARITY ERROR vs CODE  
(+85°C, AVDD = 5V, VREF = 2.5V, GAIN = 1)  
(+85°C, AVDD = 2.7V, VREF = 1.25V, GAIN = 1)  
8.0  
6.0  
4.0  
2.0  
0
8.0  
6.0  
4.0  
2.0  
0
2.0  
4.0  
6.0  
8.0  
2.0  
4.0  
6.0  
8.0  
1.0  
0.8  
0.6  
0.4  
0.2  
0
1.0  
0.8  
0.6  
0.4  
0.2  
0
0.2  
0.4  
0.6  
0.8  
1.0  
0.2  
0.4  
0.6  
0.8  
1.0  
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
0
512 1024 1536 2048 2560 3072 3584 4096  
Code  
Figure 25.  
Figure 26.  
NORMALIZED OFFSET ERROR  
vs TEMPERATURE  
NORMALIZED GAIN ERROR  
vs TEMPERATURE  
2.0  
1.5  
1.0  
0.5  
0
0.10  
0.05  
0
External 2.5V Reference  
AVDD = 5V  
External 2.5V Reference  
AVDD = 5V  
Gain = +1  
Gain = +2  
0.5  
1.0  
1.5  
2.0  
0.05  
0.10  
20  
20  
60  
40  
60  
40  
0
20  
40  
60  
80  
100  
0
20  
40  
60  
80  
100  
_
_
Temperature ( C)  
Temperature ( C)  
Figure 27.  
Figure 28.  
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TYPICAL CHARACTERISTICS: DIGITAL-TO-ANALOG CONVERTER (DAC) (continued)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
VOUT vs  
VOUT vs  
SOURCING AND SINKING CURRENT  
SOURCING AND SINKING CURRENT  
6.0  
5.0  
4.0  
3.0  
2.0  
1.0  
0
3.0  
2.5  
2.0  
1.5  
1.0  
0.5  
0
Sourcing Current  
Sinking Current  
Sourcing Current  
Sinking Current  
AVDD = 5V  
VREF = 2.5V  
Gain = +2  
AVDD = 2.7V  
VREF = 1.25V  
Gain = +2  
0
2
4
6
8
10  
12  
14  
16  
18 20  
0
2
4
6
8
10  
12  
14  
16  
18 20  
Sourcing or Sinking Current (mA)  
Sourcing or Sinking Current (mA)  
Figure 29.  
Figure 30.  
DAC SETTLING TIME  
(GAIN = +2)  
DAC SETTLING TIME  
(GAIN = +1)  
CL = 10pF  
CL = 10pF  
RL= 10k  
RL= 10k  
Code 4095  
Code 3932  
VREF = 2.5V  
VREF = 2.5V  
Input  
Input  
Code 256  
Code 512  
Settling  
Detail  
Settling  
Detail  
µ
Time (1 s/div)  
µ
Time (1 s/div)  
Figure 31.  
Figure 32.  
DAC POWER-ON RESET  
TO 0V  
5V  
AVDD, DVDD,  
BVDD, RESET  
0V  
0V  
DAC Output  
µ
Time (100 s/div)  
Figure 33.  
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TYPICAL CHARACTERISTICS: PRECISION CURRENT SOURCE  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
100μA CURRENT SOURCE  
PRECISION_I_OUTPUT  
vs  
vs  
TEMPERATURE  
COMPLIANCE VOLTAGE  
0.5  
0.4  
0.3  
0.2  
0.1  
0
0.1  
0
AVDD = 5V  
VREF = 2.5V  
AVDD / VREF = 5V / 2.5V  
or 3V / 1.25V  
0.1  
0.2  
0.3  
0.4  
0.5  
0.6  
0.7  
0.8  
0.9  
1.0  
1.1  
1.2  
µ
10 A (nom)  
0.1  
0.2  
0.3  
0.4  
0.5  
10mA (nom)  
1mA (nom)  
µ
100 A (nom)  
25  
50  
4.00  
4.25  
4.5  
4.75  
5.0  
0
25  
50  
75  
100  
_
Temperature ( C)  
Compliance Voltage (V)  
Figure 34.  
Figure 35.  
PRECISION_I_OUTPUT  
vs  
COMPLIANCE VOLTAGE  
CURRENT SOURCE PRODUCTION DISTRIBUTION  
(2.5V EXTERNAL REFERENCE)  
0.1  
0
70  
AVDD = 2.7V  
VREF = 1.25V  
60  
50  
40  
30  
20  
10  
0
0.1  
µ
10 A (nom)  
0.2  
0.3  
0.4  
0.5  
0.6  
0.7  
0.8  
0.9  
1.0  
1.1  
1.2  
10mA (nom)  
µ
100 A (nom)  
1mA (nom)  
2.00  
1.60  
1.80  
2.20  
2.40  
2.60  
2.80  
Compliance Voltage (V)  
µ
Current ( A)  
Figure 36.  
Figure 37.  
18  
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TYPICAL CHARACTERISTICS: PRECISION CURRENT SOURCE (continued)  
At +25°C, AVDD = DVDD = 5V, unless otherwise noted.  
CURRENT SOURCE PRODUCTION DISTRIBUTION  
(1.25V EXTERNAL REFERENCE)  
70  
60  
50  
40  
30  
20  
10  
0
µ
Current ( A)  
Figure 38.  
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APPLICATION INFORMATION  
DIGITAL INTERFACE  
The AMC7823 communicates through a standard SPI bus. The SPI allows full-duplex, synchronous, serial  
communication between a host processor (the master) and peripheral devices (slaves). The SPI master  
generates the synchronizing clock and initiates transmissions. SPI slave devices, such as the AMC7823, depend  
on a master to start and synchronize transmissions.  
A transmission begins when initiated by an SPI master. A word from the master is shifted into the AMC7823  
through the MOSI pin under the control of the master serial clock, SCLK. A word from an AMC7823 register is  
shifted out from the MISO pin under the control of SCLK as well.  
The idle state of the serial clock for the AMC7823 is low, which corresponds to a clock polarity setting of 0  
(typical microprocessor SPI control bit CPOL = '0'). The AMC7823 interface is designed with a clock phase  
setting of 1 (typical microprocessor SPI control bit CPHA = '1'). In both the master and the slave, data are shifted  
out on the rising edge of SCLK and sampled on the falling edge of SCLK where data are stable. The master  
begins driving the MOSI pin on the first rising edge of SCLK after SS is activated (low).  
To write data into AMC7823, the host activates the slave select signal (SS = low) and issues a WRITE command  
to start the data transmission. The AMC7823 always interprets the first word (from the host) immediately  
following the falling edge of SS signal as a command. The data to be written into the AMC7823 follow the  
command. The slave select pin (SS) must remain low until all data are transmitted (see Figure 39). Otherwise,  
the WRITE operation is terminated. Likewise, to read data from AMC7823, the host activates the slave select  
signal and sends a READ command. The AMC7823 then sends data out through the MISO pin under the control  
of SCLK. The slave select pin must remain low until all data are shifted out (see Figure 39). Otherwise, the  
transmission is terminated, and all remaining data (if any) are ignored.  
When the operation is terminated, the master must issue a new command to start a new operation.  
All registers in the AMC7823 are 16-bit. It takes 16 clock pulses of SCLK to transfer one data or command word.  
All data are transferred into (or out of) the AMC7823 through an internal serial-parallel (parallel-serial) register. If  
SS is deactivated (that is, goes high) before the 16th clock finishes, the incomplete transfer is terminated  
immediately and the data being transferred are ignored. In a write operation, the data are not written into the  
AMC7823 register. In a read operation, the remaining data bits are not shifted out, and the data must be ignored.  
AMC7823 COMMUNICATION PROTOCOL  
With the exception of two external trigger pins, an external RESET pin, and an external current setting resistor,  
the AMC7823 is entirely controlled by registers. Reading from and writing to these registers is accomplished by  
issuing a 16-bit command word followed immediately by data for a single register or for a range of registers. This  
command word is constructed as shown in the Command Format table. The data word(s) format for the target  
register(s) are illustrated in subsequent pages of this document.  
Command Format  
Bit 15 Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
MSB  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
X
Bit 4  
Bit 3  
Bit 2  
Bit 1  
Bit 0  
LSB  
R/W  
X
PG1  
PG0  
X
SADR SADR SADR SADR SADR  
EADR EADR EADR EADR EADR  
4
3
2
1
0
4
3
2
1
0
X : Don't Care  
Where:  
R/W: Data flow direction bit.  
R/W = '1'. Read operation. Data are transferred from AMC7823 to the host.  
R/W = '0'. Write operation. Data are transferred from the host to AMC7823.  
PG1 – PG0: Memory page of addressed register(s) (see Table 1).  
SADR4 – SADR0: Starting address of register(s) on selected page.  
EADR4 – EADR0: Ending address of register(s) on selected page.  
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NOTE: If the ending address is equal to or smaller than the starting address, only the starting address is  
accessed. In this case, the operation applies only to the starting address; all remaining data and memory  
locations (if any) are ignored. In this manner, a single register may be addressed by setting [EADR4:EADR0] =  
00000 or [SADR4:SADR0] [EADR4:EADR0].  
Table 1. Page Addressing  
PG1  
PG0  
PAGE ADDRESS  
0
0
1
1
0
1
0
1
0
1
Reserved  
Reserved  
For example, to read the register with address 0x00 on page 0, the host processor must send the AMC7823 the  
command 0x8000; this command specifies a read operation on page 0, address 0. After sending the command,  
the host reads one data word. To read the registers 0x02 to 0x07 on page 0 (ADC Data-2 to ADC Data-7), the  
host must send 0x8087 first, and then clock six data words sequentially out of the AMC7823. The first data word  
is from 0x02, the second from 0x03, and the sixth from 0x07. If the host continues clocking data out after reading  
the last location [EADR4:EADR0], the value 0x0000 is output until the operation stops. However, if the host  
deactivates SS before reading the last register, the operation is terminated and all remaining registers are  
ignored.  
Likewise, to load data into the registers with addresses 0x03 to 0x05 on page 1 (DAC-3 Data Register to DAC-5  
Data Register), the host sends command 0x10C5 followed sequentially by three data words. The first word is  
written into 0x03 of page 1, the second goes to 0x04, and the third goes to 0x05. If the host continues to transfer  
data into AMC7823 after writing the last location [EADR4:EADR0], all these data are ignored until the operation  
stops. However, if the host deactivates SS before writing the last location, the operation is terminated and all  
remaining locations are ignored.  
See the AMC7823 Memory Map (Table 2) for details of register locations.  
Figure 39 shows an example of a complete data transaction between the host processor and the AMC7823.  
SS  
SCLK  
MOSI  
Write Command  
1st Data [SADR4:SADR0]  
Last Data [EADR4:EADR0]  
Data Written into AMC7823 Registers  
SS  
SCLK  
MOSI  
MISO  
Read Command  
Don’t Care  
Hi−Z  
Hi−Z  
1st Data [SADR4:SADR0]  
Last Data [EADR4:EADR0]  
Data Read from AMC7823 Registers  
Figure 39. Write and Read Operations of the AMC7823 Interface  
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AMC7823 MEMORY MAP  
The AMC7823 has several 16-bit registers separated into two pages of memory, Page 0 and Page 1. The  
memory map is shown in Table 2. Locations that are marked Reserved read back 0x0000 if they are read by the  
host. Writing to these locations has no effect. Figure 40 explains the Read/Write operation.  
Table 2. AMC7823 Memory Map  
Page 0: Data/Status Registers  
Page 1: Control/Setting Registers  
Register Name  
Address R/W  
Default  
Register Name  
Address  
00  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Default  
0x0000  
0x0000  
0x0000  
0x0000  
0x0000  
0x0000  
0x0000  
0x0000  
0x0000  
0x0000  
0x4000  
0x0000  
0x0000  
0x0000  
0x0FFF  
0x0000  
0x0FFF  
0x0000  
0x0FFF  
0x0000  
0x0FFF  
0x0000  
00  
01  
02  
03  
04  
05  
06  
07  
08  
09  
0A  
0B  
0C  
0D  
0E  
0F  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
1A  
1B  
1C  
1D  
1E  
1F  
R
R
0x0000 ADC-0 Data  
0x0000 ADC-1 Data  
0x0000 ADC-2 Data  
0x0000 ADC-3 Data  
0x0000 ADC-4 Data  
0x0000 ADC-5 Data  
0x0000 ADC-6 Data  
0x0000 ADC-7 Data  
0x0000 ADC-8 Data  
0x0000 ALR Register  
0xFFFF GPIO Register  
Reserved  
DAC-0 Data  
DAC-1 Data  
DAC-2 Data  
DAC-3 Data  
DAC-4 Data  
DAC-5 Data  
DAC-6 Data  
DAC-7 Data  
LOAD DAC  
01  
R
02  
R
03  
R
04  
R
05  
R
06  
R
07  
R
08  
R
09  
DAC Configuration  
AMC Status/Configuration  
ADC Control  
RESET  
R/W  
0A  
0B  
0C  
0D  
0E  
0F  
10  
Reserved  
Reserved  
Power-Down  
Threshold-Hi-0  
Threshold-Low-0  
Threshold-Hi-1  
Threshold-Low-1  
Threshold-Hi-2  
Threshold-Low-2  
Threshold-Hi-3  
Threshold-Low-3  
Reserved  
Reserved  
Reserved  
Reserved  
Reserved  
11  
Reserved  
12  
Reserved  
13  
Reserved  
14  
Reserved  
15  
Reserved  
16  
Reserved  
17  
Reserved  
Reserved  
18  
Reserved  
Reserved  
19  
Reserved  
Reserved  
1A  
1B  
1C  
1D  
1E  
1F  
Reserved  
Reserved  
Reserved  
Reserved  
Reserved  
Reserved  
Reserved  
Reserved  
R
0xE000  
Part Revision Number  
Reserved  
Reserved  
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RECEIVING  
COMMAND  
READ OPERATION  
[ADR] = [SADR]  
WRITE OPERATION  
(1)  
Yes  
No  
(1)  
READ ?  
[ADR] = [SADR]  
READ DATA  
[ADR] + 1  
WRITE DATA  
[ADR] + 1  
(3)  
(3)  
Yes  
Is SS deactivated?  
Yes  
Is SS deactivated?  
No  
No  
(2)  
(2)  
[ADR] > [EADR]  
Yes  
No  
No  
[ADR] > [EADR]  
Send  
Output  
0x0000  
Ignore any  
remaining data  
Waiting for new  
command  
(1) [SADR] represents the start address, which is specified by bits [PG1:PG0] and [SADR4:SADR0] in the command  
word. [ADR] represents the current address.  
(2) [EADR] represents the end address, which is specified by bits [PG0:PG1] and [EADR4:EADR0] in the command  
word.  
(3) Host ends data transfer by deactivating SS.  
Figure 40. Read/Write Operations  
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ADC OPERATION (See AMC Status/Configuration Register and ADC Control Register)  
CMOD of ADC Control Register defines  
Out-of-Range Alarm of  
conversion mode.  
first four inputs being  
converted  
For Direct-Mode (CMOD = 0), each channel  
being converted is accessed one time after  
triggered.  
Out-of-Range  
ALARM  
Double-Buffered  
For Auto-Mode (CMOD = 1), all channels  
being converted are accessed repeatedly  
after triggered.  
MUX  
ADC Data Register  
To Shifter  
Register  
ADC−0  
DATA  
ADC−0  
TMPRY  
CH0  
CH3  
External trigger works in Direct-Mode only.  
After conversion of CH-n finished,  
ADC-n TMPRY register is updated  
immediately.  
ADC  
TMPRY register is a temporary registe.r  
CH7  
CH8  
ADC-n DA  
All  
TA registers are  
updated simultaneously when the  
conversion of the last channel  
selected is completed. (1)  
(temperature)  
Bit GREF, effective for  
Internal Reference only(2)  
ADC−6  
DATA  
ADC−6  
TMPRY  
Internal Trigger generated by  
Writing ADC Control Register  
To Shift  
0
1
Register  
CONVERT, External  
ADC−7  
TMPRY  
ADC−7  
DATA  
Bit ECNVT  
ADC−8  
DATA  
ADC−8  
TMPRY  
Bit ECNVT of AMC Status and Configuration Register  
selects the trigger signal.  
Bit DAVF, Pin DAV  
ECNVT = 1, Rising Edge of External CONVERT triggers ADC  
ECNVT = 0, Writing ADC Control Register triggers ADC  
Bit DAVF and Pin DAV indicate new data available.  
After ADC-n Data are Updated, DAVF is set to ‘1’.  
Pin DAV Goes Low (Direct-Mode) or Sends 2 ms  
Pulse (Auto-Mode). Refer to Figure 42, Figure 43 and  
Figure 44.  
(1) To avoid conflict, the data are not loaded into ADC-n data register from ADC-n temporary register until the data  
transfer from the ADC-n data register to the shift register (if any) finishes.  
(2) When the internal reference is selected, the bit GREF determines the input range: GREF = '0', 0 to 2.5V; GREF = '1',  
0 to 5V (for 5V supply only). When an external reference is selected, the input range is 0 to 2 × VREF. The input  
cannot be above AVDD  
.
Figure 41. ADC Structure  
The ADC has nine analog inputs. Channels CH0 through CH7 receive external analog inputs. CH8 is dedicated  
to the on-chip temperature sensor (see On-chip Temperature Sensor section).  
ADC Trigger Signals (see AMC Status/Configuration Register)  
The ADC can be triggered externally (external trigger mode) or internally (internal trigger mode). Bit ECNVT  
(Enable CONVERT) of the AMC Status/Configuration Register determines which mode is used. When ECNVT is  
set to '1', the ADC works in external trigger mode and the rising edge of the external signal CONVERT initiates  
data conversion. When ECNVT is cleared to '0', the ADC is in internal trigger mode, and writing to the ADC  
Control Register initiates conversion.  
After the ADC is triggered, a group of analog inputs (up to nine channels may be specified) are multiplexed and  
each channel is converted. The starting and ending addresses of the group of channels are specified by the bits  
[SA3:SA0] and [EA3:EA0], respectively, in the ADC Control Register (see ADC Control Register for details). The  
specified channels are converted sequentially from the starting to the ending address according to Table 12  
(Analog Input Channel Address Map) and Table 13 (Analog Input Channel Range).  
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Conversion Mode  
When internal trigger mode is selected (ECNVT = '0'), two types of ADC conversion are available: direct-mode  
and auto-mode. The bit CMODE (Conversion MODE) of the ADC Control Register specifies the conversion  
mode. When external trigger mode is selected (ECNVT = '1'), only direct-mode conversion is available. In this  
case, bit CMODE in the ADC Control Register is ignored. (See Table 3.)  
In direct-mode, each analog channel within the specified group is converted a single time. After the last channel  
is converted, the ADC goes into idle state and waits for a new trigger.  
Auto-mode is a continuous operation. In auto-mode, each analog channel within the specified group is converted  
sequentially from [SA3:SA0] to [EA3:EA0] and repeatedly until one of the following events occur:  
a new internal trigger is issued;  
the conversion mode is changed to direct-mode by rewriting the ADC Control Register; or  
the external trigger is enabled by rewriting the AMC Status/Configuration Register.  
When a new internal trigger is issued, a new conversion process starts.  
Table 3 summarizes the ADC conversion modes. Note that the ending address must not be less than the starting  
address. Otherwise, the ADC conversion sequence may not be correct.  
Table 3. ADC Conversion Modes  
ECNVT OF AMC STATUS/  
CMODE OF  
CONFIGURATION REGISTER  
ADC CONTROL REGISTER  
ADC CONVERSION MODE  
External Trigger, Direct-Mode  
1
0
0
0
1
Internal Trigger, Direct-Mode  
Internal Trigger Auto-Mode  
Double-Buffered ADC Data Register  
The host can access all nine double-buffered ADC Data registers. The conversion result from the analog input  
with the channel address n is stored in the ADC-n Data register. When the conversion of an individual channel is  
completed, the data is immediately transferred into the corresponding ADC-n temporary (TMPRY) register, the  
first stage of the data buffer. When the conversion of the last channel ( [EA3:EA0] ) finishes, all data in ADC-n  
TMPRY registers are transferred simultaneously into the corresponding ADC-n Data registers, the second stage  
of the data buffer. However, if a data transfer is in progress between an ADC-n Data Register and the AMC Shift  
Register, this ADC-n Data Register is not updated until the data transfer is complete. The conversion result from  
channel address n is stored in the ADC-n Data Register. For example, the result from channel [0x04] is stored in  
the ADC-4 Data Register, and the result from channel [0x07] is stored in the ADC-7 Data Register. The ADC-8  
Data Register is used to store on-chip temperature measurement data (see the On-chip Temperature Sensor).  
SCLK Clock Noise  
The host activates the slave select signal SS (low) to access the AMC7823. When SS is high, the SCLK clock is  
blocked. To avoid noise caused by SCLK clock, deactivate SS (high) for at least the conversion process time  
immediately after the ADC conversion starts.  
Handshaking with the Host (see AMC Status/Configuration Register)  
The DAV pin and the bit DAVF (Data Available Flag) of the AMC Status/Configuration Register provide  
handshaking with the host. Pin and bit status depend on the conversion mode (direct or auto). In direct-mode,  
after ADC-n Data registers of all of the selected channels are updated, the DAVF bit in the AMC  
Status/Configuration Register is set immediately to '1', and the DAV pin is active (low) to signify new data are  
available. Reading the ADC-n Data Register or restarting the ADC clears bit DAVF to '0' and deactivates the  
DAV pin (high).  
In auto-mode, after ADC-n Data registers of the selected channels are updated, a pulse of 2μs (low) appears on  
the DAV pin to signify new data are available. However, bit DAVF is always cleared to '0' in auto-mode.  
Figure 42, Figure 43 and Figure 44 illustrate the handshaking protocol.  
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SS  
SS  
WRITE ADC  
CONTROL Register  
WRITE ADC  
CONTROL Register  
1st Internal  
Trigger  
2nd Internal  
Trigger  
WRITE ADC  
CONTROL Register  
Internal Trigger  
MOSI  
DAV  
MOSI  
DAV  
2ms  
1st Conversions,  
[SA3:SA0] to [EA3:EA0]  
2nd Conversions,  
[SA3:SA0] to [EA3:EA0]  
1st Round of 2nd Round of  
Conversions, Conversions,  
[SA3:SA0] to [EA3:EA0] [SA3:SA0] to [EA3:EA0]  
Figure 42. Internal Trigger, Direct-Mode  
Figure 43. Internal Trigger, Auto-Mode  
Rising Edge  
Starts Conversions  
1st Trigger  
2nd Trigger  
3rd Trigger  
CONVERT  
DAV  
1st Conversions, of  
Analog Inputs, From  
[SA3:SA0] to [EA3:EA0]  
2nd Conversions,  
[SA3:SA0] to [EA3:EA0] [SA3:SA0] to [EA3:EA0]  
3rd Conversions,  
Figure 44. External Trigger  
Analog Input Out-of-Range Detection (see Analog Input Out-of-Range Alarm Section)  
The first four analog inputs of the group defined by the bits [SA3:SA0] and [EA3:EA0] are implemented with out-  
of-range detection. When an input is out of the preset range, the corresponding alarm flag, bit ALR-n of the ALR  
(Alarm) Register is set. If any of the four inputs are out of range, the global out-of-range pin GALR goes low.  
Four GPIO pins (GPIO-0, GPIO-1, GPIO-2 and GPIO-3) can be configured as out-of-range indicators for each of  
the first four analog inputs. See the Analog Input Out-of-Range Alarm and Digital I/O sections for more details.  
Full-Scale Range of Analog Input  
The full-scale range of the analog input is 2 × VREF, but must not exceed the supply value AVDD. Input saturation  
can occur if the analog input exceeds this value.  
The internal reference or an externally applied reference may be used as VREF. The bit SREF in the AMC  
Status/Configuration Register controls the selection of the internal reference. When SREF = '0' (power-up default  
condition), the internal reference is selected and is internally applied through a 10kresistor to pin 21. When  
SREF = '1', the internal reference is disconnected from pin 21, and an external reference may be applied. See  
Figure 48.  
Table 4 shows the configuration of the ADC input range.  
Table 4. Configuration of ADC Input Range  
BIT  
GREF  
BIT  
SREF  
ADC INPUT  
RANGE  
DESCRIPTION  
0
1
0
0
0 to 2.5V  
0 to 5V  
Internal reference, 1.25V  
Internal reference, 2.5V, AVDD = 5V only  
Don't  
care  
External reference VREF. 2 × VREF must not be greater than AVDD  
Set SREF = 1 when applying external reference.  
.
1
0 to 2 × VREF  
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The bit GREF in the AMC Status/Configuration Register selects between two preset internal reference values.  
When GREF = '0' (power-up default condition), the internal reference is set to 1.25V. When GREF = '1', the  
internal reference is 2.5V. GREF must be cleared to '0' when the power supply is less than 5V.  
When an external reference is applied, the input range is 0 to 2 × VREF, and is not affected by the bit GREF. In  
this case, ideally SREF has been set to '1' and the internal reference is disconnected. This condition is preferred  
for operating the AMC7823. If SREF = '0', the external reference overrides the internal reference, provided it can  
accommodate a 10kload. To avoid input saturation, the external reference must not be greater than 2.5V when  
the analog power supply is 5V, and must not be greater than 1.25V when the supply is 3V.  
Figure 45 illustrates the ADC operation.  
New ADC Conversion Trigger  
Clear DAVF bit in AMC  
Status/Configuration Register  
Clear all ALR-n in ALR Register  
(1)  
Set [ADR] = [SA]  
Sample  
Convert  
Update ADC-n TMPRY Register  
No  
First four channels?  
Yes  
(2)  
Drive GALR Pin Low  
Out-of-range?  
No  
Yes  
Set ALR-n Bit in ALR Register  
[ADR] + 1  
(1)  
[ADR] > [EA] ?  
Yes  
No  
Update ADC-n  
Data Register  
Auto-Mode,  
Internal Trigger only  
(4)  
Apply 2-ms Pulse (Low)  
to Pin DAV  
Auto-Mode  
No  
Yes  
(3)  
Direct-Mode  
Set DAVF bit;  
Drive DAV Pin Low  
ADC in idle  
Waiting new trigger  
(1) [SA] represents the first input channel, [EA] represents the last input channel. [ADR] represents the current input  
channel. [SA3:SA0] is the address of [SA]. [EA3:EA0] is the address of [EA].  
(2) GALR pin goes high and bits ALR-n are cleared after new ADC Conversion trigger.  
(3) After reading the ADC Data Register, bit DAVF is cleared, and the DAV pin goes high.  
(4) In Auto-mode, bit DAVF is always cleared.  
Figure 45. ADC Operation Flow Chart  
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ON-CHIP TEMPERATURE SENSOR  
The AMC7823 has an integrated temperature sensor to measure the on-chip temperature. This measurement  
relies on the characteristics of a semiconductor p-n junction operating at a known current level. The forward  
voltage of the diode (VBE) depends on the current passing through it and the junction temperature.  
Channel CH8 is dedicated to the on-chip temperature sensor. When CH8 is converted, the on-chip temperature  
measurement process is activated. Two measurements, and therefore two ADC conversions, are required to  
capture the temperature data. First, the diode is driven by current I1 (750μA) and the forward voltage VBE1 is  
measured. Next, the diode is driven by current I2 (10μA) and VBE2 is measured. The difference of these two  
voltages, ΔVBE, is stored in the ADC-8 Data Register as straight binary code. See Figure 46.  
Diode Temperature  
Sensor  
CH8 (TEMP)  
ADC  
SW2  
SW1  
I2 (10 mA)  
I1 (750 mA)  
NOTE: When CH8 is converted, two conversions are performed. During the first conversion, SW1 is turned on, SW2 is off,  
and the diode is driven by I1 (750μA). During the second conversion, SW2 is turned on, SW1 is off, and the diode is  
driven by I2 (10μA).  
Figure 46. Local Temperature Sensor Operation  
In direct-mode operation, the temperature can be measured by converting Channel CH8 only, or by converting  
several channels including Channel CH8. In auto-mode, the temperature must be measured by converting at  
least two channels including Channel CH8.  
The following equations illustrate the corresponding temperature calculation process:  
ΔVBE (mV) = decimal code (convert from ADC-8 Data Register binary code) × 1.22mV for VREF = 2.5V  
or  
ΔVBE (mV) = decimal code (convert from ADC-8 Data Register binary code) × 0.61mV for VREF = 1.25V.  
Temp (K) = 2.6 × ΔVBE (mV)  
or  
Temp (°C) = 2.6 × ΔVBE (mV) – 273K.  
The resolution of this calculation is 3.2°C/LSB when the reference voltage is 2.5V and 1.6°C/LSB for a reference  
voltage of 1.25V. The temperature sensor is powered by the reference. When the internal reference is used, a  
filter capacitor (for example, 10μF) from pin 21 (EXT_REF_IN) to AGND is recommended to improve  
temperature reading; refer to the Reference section for more information.  
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DAC OPERATION (see DAC-n Data Registers and DAC Configuration Register)  
AMC7823 has eight double-buffered DACs. The outputs of the DACs can be updated synchronously or  
individually (asynchronously). Figure 47 illustrates the generic DAC structure.  
Data to Host  
when Read  
DAC-0  
VOUT Range: 0 - VREF x Gain  
Data from  
Host  
VOUT0  
DAC-0  
Latch  
DAC-0  
Data  
Bit PDAC-0  
(Power-Down bit in Power-Down  
Register; see (1) )  
Bit SLDA-n of DAC Configuration Register determines  
when DAC-n Latch is loaded with the value of  
DAC-n Data Register.  
5 kW  
Gain = 2 if GDAC-0 = 1  
Gain = 1 if GDAC-0 = 0  
SLDA-n = 1: Latch is loaded when Synchronous  
Loading signal occurs; synchronous loading  
Bit GDAC-0  
(DAC Configuration Register)  
SLDA-n = 0: Latch is loaded immediately after  
DAC-n Data register is written; asynchronous loading  
DAC-7  
DAC-7  
Data  
Bit PDAC-7 (Power-Down bit  
in Power-Down Register)  
BB00h  
Internal ILDAC  
Synchronous  
Loading Signal  
Load DAC  
Register  
Bit GDAC−7  
External ELDAC  
Loads all DAC-n latches when corresponding SLDA-n is set to ‘1’.  
Does not affect DAC-n when SLDA-n is cleared to ‘0’.  
(1) When PDAC-n = 0, DAC-n is in power-down mode; the output buffer of DAC-n connects to ground through a 5kΩ  
load.  
Figure 47. DAC Structure  
Double-Buffered Data Register  
All eight DAC data registers are double-buffered. Each DAC has an internal latch preceded by an input register.  
Data are initially written to an individual DAC-n Data register and then transferred to its corresponding DAC-n  
Latch. When the DAC-n Latch is updated, the output of DAC-n changes to the newly set value. When the host  
reads the register memory map location labeled DAC-n Data, the value held in the DAC-n Latch is returned (not  
the value held in the input DAC-n Data Register).  
Synchronous Load, Asynchronous Load, and Output Updating  
The DAC latches can be updated synchronously or asynchronously. The bit SLDA-n (Synchronous Load) of the  
DAC Configuration Register is used to specify the DAC updating mode.  
Asynchronous mode is active when SLDA-n is cleared to '0'. Immediately after writing to the DAC-n Data  
Register, its data are transferred to the corresponding DAC-n Latch Register, and the output of DAC-n changes  
accordingly.  
Synchronous mode is selected when the bit SLDA-n is set to '1'. The value of the DAC-n Data Register is  
transferred to the DAC-n Latch only after an active DAC synchronous loading signal occurs, which immediately  
updates the DAC-n output. Under synchronous loading operation, writing data into a DAC-n Data Register  
changes only the value in that register, but not the content of DAC-n Latch nor the output of DAC-n, until the  
synchronous load signal occurs.  
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The DAC synchronous load signal can be the rising edge of the external signal ELDAC, or the internal signal  
ILDAC. Write BB00h into the Load DAC Register to generate ILDAC. When the DAC synchronous load signal  
occurs, all DACs with the bit SLDA-n set to '1' are updated simultaneously with the value of the corresponding  
DAC-n Data register. By setting the bit SLDA-n properly, several DACs can be updated at the same time. For  
example, to update DAC0 and DAC1 synchronously, the host sets the bits SLDA-0 and SLDA-1 to '1' first, then  
writes the proper values into the DAC-0 Data and DAC-1 Data registers, respectively. After this presetting, the  
host activates ELDAC (or ILDAC) to load DAC0 and DAC1 simultaneously. The outputs of DAC0 and DAC1  
change at the same time.  
Table 5 summarizes methods to update the output of DAC-n.  
Table 5. DAC-n Output Update Summary  
WRITING LOAD  
DAC REGISTER  
EXTERNAL  
ELDAC SIGNAL  
BIT SLDA-n  
OPERATION  
0
Don't care  
Don't care  
Update DAC-n individually.  
DAC-n Latch and DAC-n Output are immediately updated after writing to DAC-n  
Data Register  
1
1
Write 0xBB00  
0
Simultaneously update all DAC by internal trigger .  
Writing 0xBB00 generates internal load DAC trigger signal ILDAC, which causes  
DAC-n Latches and DAC-n Outputs to be updated with the contents of  
corresponding DAC-n Data Register.  
No  
Rising edge  
Simultaneously update all DACs by external trigger ELDAC.  
Rising edge of ELDAC causes DAC-n Latches and DAC-n Outputs to be  
updated with the contents of corresponding DAC-n Data Register.  
Full-Scale Output Range  
The full-scale output range of each DAC is set by the product of the value of the reference voltage times the gain  
of the DAC output buffer, VREF × Gain. The bit GDAC-n (Gain of DAC-n output buffer) of the DAC Configuration  
Register sets the gain of the individual DAC-n output buffer. The gain is unity (1) when GDAC-n is cleared to '0',  
and is 2 when GDAC-n is set to '1'.  
The value of VREF may be controlled by bits SREF and GREF in the AMC Status/Configuration Register and by  
the choice of internal or external reference. For a similar description, see the Full-Scale Range of Analog Input in  
the ADC Operation section.  
Full-scale output range of each DAC is limited by the analog power supply because the DAC output buffer  
cannot exceed AVDD. Table 6 shows how to configure the DAC output range.  
Table 6. Configuration of DAC Output Range  
OUTPUT RANGE  
SREF  
GREF  
GDAC-n  
REFERENCE  
Internal 1.25V  
Internal 1.25V  
Internal 2.5V  
Internal 2.5V  
AVDD = 3V  
0V to 1.25V  
AVDD = 5V  
0V to 1.25V  
0V to 2.5V  
0
0
0
0
0
0
1
1
0
1
0
1
0V to 2.5V  
0V to 2.5V  
0V to 2.5V  
Saturated at 3V  
0V to External VREF  
External VREF AVDD  
0V to 5V  
Don't  
care  
,
0V to External VREF,  
External VREF AVDD  
1
1
0
1
External VREF  
External VREF  
Don't  
care  
0V to External VREF × 2  
2 × External VREF AVDD  
0V to External VREF × 2  
2 × External VREF AVDD  
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After power-on or reset, all DAC-n Data Registers and all DAC-n Latches are cleared to '0'. This clearing process  
results in all DAC outputs at 0V, gain of unity, and a full-scale output range preset to either 1.25V or equal to the  
external reference (if it is applied) because bits SREF and GREF are also cleared to '0'.  
Zero Code Output Value  
Each DAC buffer is clamped to prevent the output from going to 0V. Thus, when the input code is 000h, the  
output is typically 15mV to 20mV. This output keeps the closed-loop DAC output buffer in an active, stable  
operating regime, allowing it to immediately respond to an input that produces an output typically greater than  
20mV. Near-zero-volt output for a particular DAC-n may be achieved by clearing bit PDAC-n to '0' in the Power-  
Down register.  
POWER-DOWN MODE  
The AMC7823 is implemented with power-down mode. Bits in the Power-Down Register control power applied to  
the ADC, each DAC output buffer, the output amplifier of the precision current source, and the reference buffer.  
The reference buffer drives all the DAC resistor strings and supplies reference voltage to the precision current  
source. After power-on reset or any forced hardware or software reset, the Power-Down Register is cleared, and  
all these specified components are in power-down mode.  
In power-down mode, most of the linear circuitry is shut down. The ADC halts conversions, output current of the  
precision current source drops to zero, and each external DAC output pin is switched from the DAC output buffer  
to analog ground through an internal 5kresistor. The internal reference and the internal oscillator remain  
powered to facilitate rapid recovery from power-down mode.  
None of the bits in the Power-Down Register affect the digital logic. All digital signals (such as the SPI interface,  
RESET, ELDAC, ALR, and all GPIOs) still work normally in any power-down condition. In power-down mode, the  
host can read registers to get information, or write to registers to change settings. No write operation can start  
the ADC (if the ADC is in power-down), or change the DAC output (if the DAC is in power-down), but write  
operations can update register values. The new register values are effective immediately upon exiting the power-  
down mode. In this way, the host can preset DACs and the ADC before a wake-up call.  
The contents of all Page 1 addresses (see Table 2) do not change when entering or exiting power-down mode.  
The contents of the ADC registers and the alarm information in the ALR and GPIO Registers of Page 0 do not  
change when entering or exiting power-down mode if the ADC is in direct mode before powering down. To  
avoid losing ADC register content and alarm information in the ALR and GPIO Registers while the ADC is  
powered down, do not issue a convert command during power-down mode. General-purpose I/O data are not  
affected. For details, see the sections on the ALR Register and the GPIO Register.  
For power-down mode details, see the Power-Down Register section.  
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REFERENCE  
The AMC7823 requires a reference voltage to drive the ADC, the DACs, and the precision current source. It can  
accommodate the application of an external reference voltage, or it can supply reference from an internal  
bandgap voltage circuit as shown in Figure 48. Pin 21, EXT_REF_IN, is common to either source. An internal  
10kresistor connects the internal reference source to pin 21. This pin provides a point for noise filtering by  
placing a capacitor, if desired, from the pin to analog ground. The time constant of this filter is [ (10k) ×  
(CFILTER) ]. The resistor also allows an external reference applied to pin 21 to override the internal reference,  
provided it can drive the 10kload. The filter capacitor can be 10μF when the internal reference is selected.  
When using an external reference, it is recommended to use a buffered reference (such as the REF5025).  
C Filter  
21  
1.25 V  
10 kW  
Bandgap  
Reference  
A1  
2.5 V  
Bit  
GREF = 0  
Bit  
SREF = 1  
To DACs  
(Refer to diagram  
of Current Source,  
Figure 49)  
Buffer and  
Controller  
A2  
To Precision  
Current Source  
To ADC  
Figure 48. Reference  
Logic bits SREF and GREF of the AMC Status/Configuration Register specify operation of the internal reference  
and also should be considered when applying an external reference, as explained below. These bits also provide  
information to the precision current source and are used in configuring that source (refer to the Precision Current  
Source section for details).  
When SREF is cleared to '0' (the default or power-on reset condition), the internal reference is selected and  
connected to pin 21 by the 10kresistor. When SREF is set to '1', the internal reference is de-selected and  
disconnected from pin 21. Pin 21 then floats unless an external reference is applied.  
The bit GREF selects one of two pre-set values for the internal reference voltage. When GREF is cleared to '0',  
the internal reference voltage is +1.25V. When GREF is set to '1', the internal reference voltage is +2.5V.  
It is recommended to always set SREF to '1' when using an external source; otherwise, the external reference  
must sink or source a current of value equal to the difference in the reference voltages divided by 10k. For  
example, if SREF and GREF are both cleared to '0' and a 2.5V external reference is applied, the AMC7823 must  
unnecessarily sink 125μA.  
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PRECISION CURRENT SOURCE  
The AMC7823 provides the user with a precision current source for driving an external component such as a  
thermistor. Output current from pin 5 is set by the value of the resistor (RSET) connected from pin 4 to the analog  
supply voltage. This resistor should be close to the AMC7823 to minimize any voltage drop from the analog  
supply to the resistor. Internal closed-loop circuitry impresses a fixed voltage across the set resistor by means of  
an operational amplifier and a PMOS-follower output driver. Current through the set resistor supplies the follower.  
The follower driver supplies this current to the external load connected from PRECISION_I_OUTPUT (pin 5) to  
ground. This circuit architecture maintains high output impedance and provides wide output voltage compliance.  
See Figure 49.  
+5 V  
VSET  
RSET  
ISET_RESISTOR  
AVDD  
Reference  
Int. / Ext.  
GREF  
SREF  
PREFB  
PTS  
VSET  
Buffer and  
Control Circuit  
PRECISION_I_OUTPUT  
AMC7823  
AGND  
IO  
Figure 49. Diagram of Current Source  
In addition to the external setting resistor RSET, four logic bits—PTS and PREFB in the Power-Down Register and  
SREF and GREF in the AMC Status/Configuration Register—are used to configure the current source as well.  
Table 7 describes how to configure the current source.  
The bit PTS is the current source power-down bit. When PTS is cleared to '0', the current source is in power-  
down mode, and the output current is zero. When PTS is set to '1' and PREFB is set to '1', the current source is  
in normal operation.  
Bit SREF is the reference source selection bit. When SREF is cleared, the internal reference is selected. When  
SREF is set to '1', the internal reference is de-selected. Set SREF = '1' when an external reference is applied.  
GREF is the internal reference gain bit. PREFB is the Reference Buffer Amplifier Power-Down bit. Both bits  
provide information to the current source circuit, and affect the current source configuration.  
If the internal reference is used, and no external reference is applied to pin 21, the output current is 0.5V/RSET  
(VSET = 0.5V) or zero, depending on bits PREFB and GREF, as shown in Table 7.  
For a precise calculation, measure the voltage across the set resistor (VSET) and divide it by the precise value of  
RSET  
.
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Table 7. Precision Current Source Configuration  
SREF  
PTS  
0
PREFB  
GREF  
IO  
0
0
0
0
0
1
1
1
1
Don't care  
Don't care  
1
0
1
0
(1)  
1
Don't care  
0
1
0.5V/RSET  
(1)  
1
1
0.5V/RSET  
0
Don't care  
Don't care  
1(2)  
0
0
1
0
Don't care  
1
1
0(2)  
1(2)  
Equation 1  
Equation 1  
1
(1) VSET = 0.5V.  
(2) Make GREF = 1 for 2.5V external reference; make GREF = 0 for 1.25V external reference.  
When an external reference is used, select a reference value (VREF) close to either 1.25V or 2.5V, and write bit  
GREF low ('0') for a 1.25V reference, or write it high ('1') for a 2.5V reference. These settings make a better  
match to the applied external reference value. The output current can be calculated by Equation 1:  
(
)
VREF   0.4  
VSET  
RSET  
IOUTPUT  
+
+
(
)
1)GREF   RSET  
(1)  
The applied external reference voltage may deviate from the recommended values, but it is important to limit the  
maximum voltage applied to the set resistor to approximately 0.5V. Voltages greater than 0.5V across the set  
resistor reduce the specified compliance of the current source to the load.  
DIGITAL I/O (See the AMC Status/Configuration Register)  
The AMC7823 has four special function pins: DAV, GALR, ELDAC, and CONVERT. It also has six general I/O  
pins (GPIO-n). The GPIO-n pins are used as general digital I/O or analog input out-of-range indicators.  
The pin DAV is an output pin that indicates the completion of ADC conversions. Bit DAVF of the AMC  
Status/Configuration Register determines the status of the DAV pin. In direct-mode, after the selected group of  
input channels has been converted and the ADC has been halted, bit DAVF is set to '1' and pin DAV is driven to  
logic low (active). In auto-mode, each time the group of input channels has been sequentially converted, a 2μs  
pulse (low) appears on the DAV pin after the last channel of the group is converted. This conversion sequence is  
repeated and the pulse is repeated.  
The GALR pin is an output pin that indicates whether any of the first four analog inputs being converted are out-  
of-range. Bits ALR-n of the ALR Register determine the status of GALR pin. GALR is low (or active) if any one of  
the bits ALR-n is set to '1'. GALR is high (inactive) if and only if all bits are cleared to '0'. See Figure 50.  
DAV Pin in Direct Mode  
Bit DAVF of AMC  
Status / Configuration  
Register  
DAV Pin  
DAV Pin in Auto Mode  
DAV Pin  
[EA3:EA0] is  
Converted  
2ms Pulse  
Generator  
Bit ALR-0  
GALR Pin  
Bit ALR-1  
Bit ALR-2  
Bit ALR-3  
Figure 50. DAV Pin and GALR Pin  
The CONVERT pin is an input pin for the external ADC trigger signal. When bit ECNVT of the AMC  
Status/Configuration Register is set to '1', the AMC7823 works in external trigger mode. The rising edge of  
CONVERT starts the ADC conversion.  
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The ELDAC pin is an input pin for the external DAC synchronous load signal. The rising edge of ELDAC updates  
all DAC-n simultaneously that have the corresponding bit SLDA-n set to '1'.  
The AMC7823 has six GPIO pins, GPIO-n (n = 0, 1, 2, 3, 4, 5). Pins GPIO-4 and GPIO-5 are dedicated to  
general bidirectional digital I/O signals. The remaining pins (n = 0, 1, 2, 3) are dual-purpose pins, and can be  
programmed as either bidirectional GPIO or ALR (out-of-range alarm) indicators. Figure 51 shows the pin  
structure of GPIO-4 and GPIO-5. See Figure 52 for the pin structure of GPIO-n (n = 0, 1, 2 and 3).  
The bit IOMOD-n (n = 0, 1, 2, 3) in the GPIO register defines the function of these dual-purpose GPIO-n pins  
(see Table 8). When the corresponding IOMOD-n bit is cleared to '0', GPIO-n pins are configured as out-of-range  
indicators (denoted ALR-0, ALR-1, ALR-2, and ALR-3) for the first four analog inputs being converted. As an out-  
of-range indicator, the ALR-n pin is an output whose status is determined by bits ALR-0, ALR-1, ALR-2, and  
ALR-3 of the ALR Register. When ALR-n is set to '1', the ALR-n pin is low. When ALR-n is cleared to '0', the  
ALR-n pin is in high impedance status. When IOMOD-n is set to '1', the GPIO-n pin works as a general,  
bidirectional digital I/O pin.  
Table 8. GPIO Function  
IOMOD-n  
PIN NAME  
GPIO-0  
GPIO-1  
GPIO-2  
GPIO-3  
1
0
GPIO  
GPIO  
GPIO  
GPIO  
ALR-0  
ALR-1  
ALR-2  
ALR-3  
When the GPIO-n pin works as general, bidirectional digital I/O, it can receive an input or produce an output.  
(See Figure 51 and Figure 52.) When acting as output, its status is determined by the corresponding bit IOST-n  
(I/O Status) of the GPIO Register. The output is high impedance when bit IOST-n is set to '1' and is logic low  
when bit IOST-n is cleared to '0'. An external pull-up resistor is required when using GPIO-n as output.  
When GPIO-n acts as input, the digital value on the pin is acquired by reading the bit IOST-n.  
After power-on reset or any forced hardware or software reset, all IOMOD-n and IOST-n bits are set to '1', and all  
GPIO pins work as general I/O pins in high impedance status. See the GPIO Register for more detail.  
GPIO-n  
ENABLE  
IOST-n  
(when writing IOST-n)  
IOST-n  
(when reading IOST-n)  
Figure 51. Pin Structure of GPIO-4 and GPIO-5  
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Bit ALR-n of ALR Register  
Bit IOMOD-n  
in GPIO Register  
Bit IOST-n  
in GPIO Register  
GPIO-n  
ENABLE  
IOMOD-n = 0, ALR-n Pin  
IOMOD-n = 1, Digital I/O Pin  
Bit IOST-n  
(when reading)  
Figure 52. Pin Structure of GPIO-0, GPIO-1, GPIO-2, and GPIO-3  
ANALOG INPUT OUT-OF-RANGE ALARM (See ADC Operation)  
The AMC7823 provides out-of-range detection for the first four analog inputs of the group of inputs specified by  
the starting and ending addresses [SA3:SA0] and [EA3:EA0], respectively. Figure 53 describes the analog out-of-  
range logic. Alarm bits ALR-n in the ALR Register are set to '1' to flag an out-of-range condition. If the nth analog  
input is out of the preset range, then bit ALR-n is set to '1'. The nth alarm bit does not necessarily correspond to  
input channel address n, however. For example, if [SA3:SA0] and [EA3:EA0] of the ADC Control Register are  
0x04 and 0x07, respectively, then the channel address of the first analog input is [0x04] and the corresponding  
alarm bit is ALR-0. The address of the fourth input channel is [0x07] and its corresponding alarm bit is ALR-3.  
Only the first four analog inputs can be implemented with out-of-range detection. In this example, the addresses  
of the first four inputs implemented with out-of-range detection are [0x04], [0x05], [0x06], and [0x07],  
respectively. However, if [SA3:SA0] is equal to [0x00] and [EA3:EA0] is equal to [0x07], then the addresses of  
the first four are [0x00], [0x01], [0x02] and [0x03].  
Threshold-Hi-n  
Register  
(Upper Bound)  
+
nth Analog  
Input  
Bit ALR-n of  
ALR Register  
+
Threshold-Low-n  
Register  
(Lower Bound)  
ALR-n is always ‘0’ when  
Threshold-Low-n is equal to 0  
and Threshold-Hi-n is equal to  
full-scale of input  
ALR-0  
ALR-1  
ALR-2  
ALR-3  
GALR Pin  
NOTE: Threshold-Hi-n must not be smaller than Threshold-Low-n. Otherwise, ALR-n is always '1'.  
Figure 53. Analog Out-of-Range Alarm Logic  
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The value in the Threshold-Hi-n Register defines the upper bound threshold of the nth analog input, while the  
value in Threshold-Low-n defines the lower bound. These two bounds specify a window for the out-of-range  
detection. The out-of-range condition occurs when the input is set outside the window defined by these  
boundaries. To implement single upper-bound threshold detection, the host processor can set the upper bound  
to the desired value and the lower bound to zero. For lower-bound detection, the host can set the lower bound to  
the desired value and the upper bound to the full-scale input.  
To deactivate the alarm function (ALR-n always '0'), set the threshold registers to their default values as specified  
in Table 2.  
Note: The value of Threshold-Hi-n must not be less than the value of Threshold-Low-n; otherwise, ALR-n is  
always set to '1' and the alarm indicator is always active.  
If any out-of-range alarm occurs, the Global Alarm pin (GALR, pin 1) goes logic low. This function provides an  
interrupt to the host so that it may query the ALR Register (alarm register) to determine which channels are out-  
of-range.  
The general-purpose I/O pins, GPIO-0, GPIO-1, GPIO-2 and GPIO-3, are dual-purpose and can be configured  
as individual out-of-range alarm indicators denoted as ALR-0, ALR-1, ALR-2 and ALR-3 as discussed previously.  
Each ALR-n pin displays the logical complement of of each corresponding ALR-n bit. For example, when an  
alarm condition occurs, bit ALR-n is set to '1' and pin ALR-n goes logic low. For each GPIO-n pin configured as  
an alarm, its corresponding IOST-n bit in the GPIO Register displays the complement of bit ALR-n. For example,  
when bit ALR-n is set to '1', bit IOST-n is cleared to '0'. (Note that pins GPIO-4 and GPIO-5 are not dual-purpose,  
and are general digital I/O pins only.)  
CLEARING ALARM INDICATORS  
In summary, the alarm condition would have pin GALR (pin 1) and one or more pins ALR-n at logic low, one or  
more bits IOST-n cleared to '0', and one or more bits ALR-n set to '1'. All of these remain in alarm status until the  
alarm-causing conditions are removed and a new conversion is completed. When the ADC is operating in auto-  
mode, the alarm indicators are displayed after the first 2μs pulse on pin DAV following detection of one or more  
of the first four input channels out-of-range. The selected group of input channels is converted repeatedly and  
the alarm indicators remain constant until the offending inputs are corrected or until the threshold window levels  
are adjusted. When the alarm-causing conditions are removed, the alarm indicators are cleared after the first 2μs  
pulse on DAV following removal.  
When the ADC is operating in direct-mode, the alarm indicators are displayed after the first data valid signal  
(DAV, pin 2, at logic low) following an out-of-range condition. The alarm indicators remain constant until either  
the inputs are corrected or the threshold windows adjusted, and another convert command is issued and  
completed.  
In either operating mode, the alarm indicators may be cleared if a new conversion command is issued identifying  
a subset of input channels not containing the channel or channels out of range.  
The alarm indicators may also be cleared by a general hardware or software reset, or a power-on reset.  
POWER-ON RESET AND POWER-SUPPLY SEQUENCE  
After power-on or reset, all registers are reset to the default values (see Table 2). In order for the device to work  
properly, BVDD must not be applied before DVDD and AVDD are applied, and DVDD must not be applied before  
AVDD is applied. All three supplies must power up before the external reference voltage (if any) is applied.  
Additionally, because the DAC input shift register is not reset during a power-on reset (or during a hardware  
reset or software reset), the SS pin must not be unintentionally asserted during power-up of the device. It is  
recommended that the SS pin be connected to BVDD through a pull-up resistor to avoid improper power-up.  
Likewise, the state of the ELDAC pin must be maintained at ground potential during power-up. To ensure that the  
ESD protection circuitry of this device is not activated, all other digital pins must remain at ground potential until  
BVDD is applied.  
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REGISTERS  
This section describes each of the registers shown in the memory map of Table 2. The registers are named  
descriptively, according to their respective functions.  
NOTE: After power-on or reset, all ADC channels, all DACs, and the precision current source are in a powered-  
down state. The user must write the Power-Down Register properly in order to activate the desired components.  
For details, see the Power-Down Register section.  
AMC Status/Configuration Register (Read/Write; see Figure 50, DAV Pin and GALR Pin)  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
RSTC DAVF  
Bit 9  
X
Bit 8  
X
Bit 7  
Bit 6  
Bit 5  
Bit 4  
X
Bit 3  
X
Bit 2  
X
Bit 1  
X
X
0
X
X
SREF GREF ECNVT  
X
X : Don't Care  
RSTC  
RESET Complete Bit. This bit is set to '1' on power-up or reset. This bit can be cleared by writing  
'0' to this location. The host cannot set this bit to '1'. This bit allows the host to determine if the  
part has been configured after power-up, or if a reset has occurred to the AMC7823 without  
knowledge of the host.  
DAVF  
ADC Data Available Flag. For direct-mode only. Always cleared (set to '0') in auto-mode (see ADC  
Control Register).  
DAVF = 1: The ADC conversions are complete and new data are available.  
DAVF = 0: The ADC conversion is in progress (data is not ready) or the ADC is in Auto-Mode.  
In direct-mode, bit DAVF sets the pin DAV. DAV goes low when DAVF = 1, and goes high when  
DAVF = 0. In auto-mode, DAVF is always cleared to '0'. However, a 2μs pulse (active low)  
appears on the DAV pin when the input with ending address [EA3:EA0] is converted. DAVF is  
cleared to '0' in one of three ways: (1) reading the ADC Data Register; (2) starting a new ADC  
conversion; or (3) writing '0' to this bit.  
Bit 12  
SREF  
Read-only. Always '0'.  
Select Reference bit.  
SREF = 0 (default condition): The internal reference is selected as the chip reference. It is  
connected to pin 21, EXT_REF_IN, by a 10kresistor.  
SREF = 1: The internal reference is de-selected and disconnected from pin 21 (EXT_REF_IN).  
Pin 21 floats unless an external reference is applied. Always set SREF bit to '1' when an external  
reference is applied; otherwise, the external reference must sink or source current. The current  
value is the voltage difference between the external and internal reference divided by a 10kΩ  
resistance.  
SREF also provides information to the precision current source and is used to configure that  
source (see the Precision Current Source section for details). After power-on or reset, SREF is  
cleared to '0'.  
GREF  
Gain of the internal reference voltage (VREF). This bit selects one of two preset values for the  
internal reference voltage, but has no effect on the external reference. GREF also provides  
information to the precision current source and is used to configure that source (see the Precision  
Current Source section for details).  
GREF = 0: The internal reference voltage is +1.25V.  
GREF = 1: The internal reference voltage is +2.5V.  
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When an external reference is used and SREF is set to '1', GREF has no impact on the reference.  
However, if SREF is cleared to '0', a 10kresistor is connected between pin 21, EXT_REF_IN,  
and one of the two internal reference values dictated by the value of GREF. In this case, the  
external reference must be able to drive the 10kload. The full-scale range of the ADC input is  
equal to 2 x VREF. To avoid ADC input saturation, GREF must be cleared to '0' when AVDD is less  
than +5V and the internal reference is used. After power-on or reset, GREF is cleared to '0'.  
Table 9 specifies the ADC input range as a function of bits GREF and SREF.  
Table 9. Reference and ADC Input Range Configuration  
BIT GREF  
BIT SREF  
REFERENCE  
ADC INPUT RANGE  
0 to 2.5V  
0
1
0
0
1
Internal reference, 1.25V  
Internal reference, 2.5V, AVDD = 5V only  
External reference VREF  
2 × VREF must not be greater than AVDD  
Set SREF = '1' when applying external reference.  
0 to 5V  
Don't care  
.
0 to 2 × VREF  
.
ECNVT  
Enable CONVERT (external conversion trigger). This bit specifies the ADC trigger mode. When  
ECNVT = '1', CONVERT is enabled. The ADC is in external trigger mode. The low-to-high  
transition of the external trigger signal CONVERT triggers the ADC conversions. A write command  
to the ADC Control Register does not initiate conversion, but rather specifies the group of inputs  
to convert. After triggered by CONVERT, the AMC7823 sequentially accesses each analog input  
one time. The bits [SA3:SA0] of the ADC Control Register comprise the channel address of the  
first analog input accessed; [EA3:EA0] is the last analog input accessed. When the conversion  
finishes, the ADC is idle and waits for a new CONVERT or a new command. With an external  
trigger, the ADC always works in direct-mode (see the ADC Control Register section).  
When ECNVT = '0', CONVERT is disabled. The internal ADC trigger is used. A write command to  
the ADC Control Register generates the internal trigger and initiates ADC conversion. With an  
internal trigger, the ADC can work in either direct-mode or auto-mode (see the ADC Operation  
and ADC Control Register sections). Table 10 summarizes the ADC conversion mode  
configuration.  
After power-on or reset, DAVF, SREF, GREF, and ECNVT are cleared to '0'; RSTC is set to '1'.  
Table 10. ADC Conversion Mode Configuration  
ECNVT of AMC STATUS/  
CMODE of ADC  
CONFIGURATION REGISTER  
CONTROL REGISTER  
ADC CONVERSION MODE  
External Trigger, Direct-Mode  
Internal Trigger, Direct-Mode  
Internal Trigger, Auto-Mode  
1
0
0
0
1
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DAC Configuration Register (Read/Write)  
Bit 15  
www.ti.com  
Bit 0  
MSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
LSB  
SLDA7 SLDA6 SLDA5 SLDA4 SLDA3 SLDA2 SLDA1 SLDA0 GDAC GDAC GDAC GDAC GDAC GDAC GDAC GDAC  
7
6
5
4
3
2
1
0
SLDA-n  
DAC Synchronous Load Enable bit.  
SLDA-n = '1': Synchronous Load enabled. When the synchronous load DAC signal occurs, DAC-n  
Latch is loaded with the value of the corresponding DAC-n Data Register, and the output of DAC-  
n is updated immediately. This load signal can be the rising edge of the external signal ELDAC or  
the internal load signal ILDAC. Writing the data word 0xBB00 into the LOAD DAC Register  
generates ILDAC. A write command to the DAC-n Data Register updates that register only, and  
does not change the DAC-n output.  
SLDA-n = '0': Asynchronous Load enabled. A write command to the DAC-n Data Register  
immediately updates DAC-n Latch and the output of DAC-n. The synchronous load DAC signal  
(ILDAC or ELDAC) does not affect DAC-n.  
GDAC-n  
DAC-n Output Buffer Amplifier Gain bit.  
GDAC-n = '1': The gain of the DAC-n output buffer amplifier is equal to 2.  
GDAC-n = '0': The gain of the DAC-n output buffer amplifier is equal to 1.  
The combination of the bit GDAC-n and the reference voltage (internal or external) sets the full-scale range of  
each DAC-n.  
Table 11 describes the full-scale DAC output range as a function of bits SREF, GREF and GDAC-n.  
Table 11. Full-Scale DAC Output Range  
OUTPUT RANGE  
SREF  
GREF  
GDAC-n  
REFERENCE  
Internal 1.25V  
Internal 1.25V  
Internal 2.5V  
Internal 2.5V  
AVDD = 3V  
0V to 1.25V  
AVDD = 5V  
0V to 1.25V  
0
0
0
0
0
0
1
1
0
1
0
1
0V to 2.50V  
0V to 2.50V  
0V to 2.50V  
0V to 2.50V  
Saturated at 3V  
0V to External VREF  
External VREF AVDD  
0V to 5.00V  
Don't  
care  
,
0V to External VREF,  
External VREF AVDD  
1
1
0
1
External VREF  
External VREF  
Don't  
care  
0V to External VREF × 2  
2 × External VREF AVDD  
0V to External VREF × 2  
2 × External VREF AVDD  
When an external reference is applied, the full-scale output range of DAC-n is equal to VREF for GDAC = '0', and  
equal to 2 x VREF for GDAC-n = '1'.  
To avoid saturation, the full-scale output range of DAC-n must not be greater than AVDD. After power-on or reset,  
all bits are cleared to '0'.  
Load DAC Register (Read/Write)  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
1
Bit 8  
1
Bit 7  
0
Bit 6  
0
Bit 5  
0
Bit 4  
0
Bit 3  
0
Bit 2  
0
Bit 1  
0
1
0
1
1
1
0
0
The data word 0xBB00 (shown above) written into the LOAD DAC Register generates ILDAC, the internal load  
DAC signal. ILDAC and the external ELDAC signal work in a similar manner. ILDAC shifts data from the DAC-n  
Data register to the DAC-n Latch and updates the output for all DAC-n with the corresponding SLDA-n bit set to  
'1'. Other codes written to this register do not generate ILDAC and have no impact on any DAC-n. The LOAD  
DAC Register is cleared after ILDAC is generated. The register is also cleared after power-on or reset.  
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ADC Control Register (Read/Write; see ADC Operation and AMC Status/Configuration Register)  
This register specifies the ADC conversion mode and identifies the analog inputs to be converted. A write  
command to this register initiates conversion when the internal ADC trigger is selected (bit ECNVT = '0' in the  
AMC Status/Configuration Register). However, when the external trigger is selected (bit ECNVT = '1'), a write  
command to this register does not start the conversion, but it does identify the analog inputs to be converted.  
Internal trigger mode may employ either direct- or auto-mode conversion.  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
SA3 SA2  
Bit 9  
SA1  
Bit 8  
SA0  
Bit 7  
EA3  
Bit 6  
EA2  
Bit 5  
EA1  
Bit 4  
EA0  
Bit 3  
X
Bit 2  
X
Bit 1  
X
CMOD  
E
X
X
X
X
X : Don't Care  
CMODE  
ADC Conversion Mode bit. This bit selects between the two operating conversion modes (direct  
or auto) when the Internal trigger is active. This bit is always cleared to '0' (direct-mode) when an  
external trigger is active.  
CMODE = '0': Direct-mode. The analog inputs from [SA3:SA0] to [EA3:EA0] are converted  
sequentially (see Table 12) one time, [SA3:SA0] first and [EA3;EA0] last. When one set of  
conversions is complete, the ADC is idle and waits for a new trigger. The external trigger is  
restricted to this mode of operation only.  
CMODE = '1': Auto-mode. The analog inputs from [SA3:SA0] to [EA3:EA0] are converted  
sequentially (see Table 12) and repeatedly, [SA3:SA0] first and [EA3;EA0] last. When one set of  
conversions is complete, the ADC multiplexer returns to the starting address [SA3:SA0] and  
repeats the process. Repetitive conversions continue until auto-mode is halted by rewriting the  
ADC Control Register to direct-mode, or until the external trigger is enabled. Auto-mode works  
only for the internal trigger.  
SA3–SA0  
EA3–EA0  
The channel address of the first analog input to be converted (see Table 12).  
The channel address of the last analog input to be converted (see Table 12).  
The number of channels selected for conversion may range from one to eight. Channels in the selected range  
[SA3:SA0] to [EA3:EA0] are addressed sequentially according to the map shown in Table 12. The starting  
address [SA3:SA0] must not be greater than the ending address [EA:3:EA0]. When the internal trigger is  
selected, the staring address must be '0000' (that is, CH-0); otherwise, the ADC conversion may not be correct.  
Table 13 shows the allowed range of analog input channels for each ADC conversion mode. After power-on or  
reset, the ADC Control Register is cleared (0x0000).  
Channel CH8 is used for chip temperature measurement via the on-chip temperature sensor. It is not for external  
analog input (see the On-chip Temperature Sensor section for details).  
Table 12. Analog Input Channel Address Map  
SA3/EA3  
SA2/EA2  
SA1/EA1  
SA0/EA0  
ANALOG INPUT  
0
0
0
0
0
0
0
0
1
0
0
0
0
1
1
1
1
0
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
CH0  
CH1  
CH2  
CH3  
CH4  
CH5  
CH6  
CH7  
CH8  
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Table 13. Analog Input Channel Range  
STARTING CHANNEL  
ENDING CHANNEL  
[EA3:EA0]  
ECNVT  
CMODE  
ADC MODE  
[SA3:SA0]  
Any one from CH0 to  
CH8, but not less than  
[SA3:SA0]  
External trigger,  
direct mode  
1
0
Any one of CH0 to CH8  
Internal trigger,  
direct mode  
0
1
CH0 only. SA3:SA0 = '0000'  
CH0 only. SA3:SA0 = '0000'  
Any one  
Any one  
0
Internal trigger,  
auto mode  
ADC Data-n Registers (n = 0, 1, 2, 3, 4, 5, 6, 7, 8) (Read-Only)  
Nine ADC Data registers are available. The ADC Data-n Registers store the conversion results of the  
corresponding analog channel-n. The ADC-8 Data Register is used for the on-chip temperature sensor. The  
other registers are for external analog inputs. All ADC Data-n registers are formatted in the manner shown here.  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
ICH2 ICH1  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
ICH3  
ICH0 ADC1 ADC1 ADC9 ADC8 ADC7 ADC6 ADC5 ADC4 ADC3 ADC2 ADC1 ADC0  
1
0
ADC11–ADC0  
ICH3–ICH0  
Value of the conversion result. The data are updated when the conversion of the input  
[EA3:EA0] finishes; see the ADC Operation section for details.  
Analog Input Channel number  
After power-on or reset, all bits are cleared to '0'.  
All ADC Data-n Registers are read-only. Writing to the ADC Data-n registers does not cause any change.  
Table 14 summarizes the ADC Data-n Registers.  
Table 14. ADC Data-n Registers  
ICH3  
ICH2  
ICH1  
ICH0  
ANALOG INPUT  
0
0
0
0
0
0
0
0
1
0
0
0
0
1
1
1
1
0
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
CH0  
CH1  
CH2  
CH3  
CH4  
CH5  
CH6  
CH7  
CH8  
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DAC-n Data Registers (n = 0, 1, 2, 3, 4, 5, 6, 7) (see the DAC Operation section)  
This register is the input Data Register for DAC-n that buffers the DAC-n Latch Register. The DAC-n output is  
updated only when Latch is loaded. Under an asynchronous load (bit SLDA-n = '0' in the DAC Configuration  
Register), the value of the DAC-n Data Register is transferred into the Latch immediately after Data Register is  
written. If a synchronous load is specified (SLDA-n = '1'), then the DAC-n Latch is loaded with the value of the  
DAC-n Data Register only after a synchronous load signal occurs. This signal can be either the internal ILDAC or  
the rising edge of an external ELDAC (see DAC Operation and DAC Configuration Register discussions).  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
X
OCH2 OCH1 OCH0 DAC1 DAC1 DAC9 DAC8 DAC7 DAC6 DAC5 DAC4 DAC3 DAC2 DAC1 DAC0  
1
0
X : Don't Care  
DAC11–DAC0  
(WRITE/READ)  
In a write operation, these data bits are written into the DAC Data-n Register. However, in  
a read operation, the data bits are returned from the DAC-n Latch, not from the DAC-n  
Data Register.  
OCH2–OCH0  
DAC Address. Read-only. Writing these bits does not cause any change.  
The registers are cleared to '0' after power-on or reset. Table 15 summarizes the DAC-n Data Registers.  
Table 15. DAC-n Data Registers  
OCH2  
OCH1  
OCH0  
ANALOG OUTPUT  
DAC0  
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
DAC1  
DAC2  
DAC3  
DAC4  
DAC5  
DAC6  
DAC7  
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ALR Register (see Figure 53)  
Bit 15  
www.ti.com  
Bit 0  
MSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
Bit 8  
Bit 7  
X
Bit 6  
X
Bit 5  
X
Bit 4  
X
Bit 3  
0
Bit 2  
0
Bit 1  
LSB  
X
X
X
X
ALR-3 ALR-2 ALR-1 ALR-0  
0
0
X : Don't Care  
The first four analog inputs in the group defined by bits [SA3:SA0] and [EA3:EA0] in the ADC Control Register  
are implemented with out-of-range detection.  
[Bit 3:Bit 0]  
Must be '0' to ensure correct operation of alarm detection.  
ALR-n (READ-ONLY)  
nth analog input out-of-range status flag. These bits are read-only. Writing ALR-n  
bits has no effect.  
ALR-n = '1' when the nth analog input is out-of-range.  
ALR-n = '0' when the nth analog input is not out-of-range. ALR-n is always '0' when  
following conditions hold: the value of Threshold-Low-n Register is equal to '0', and  
the Threshold-Hi-n Register is equal to the full-scale value of the input.  
NOTE: To avoid loss of alarm data during power-down of the ADC, change to direct conversion mode (see ADC  
Control Register) before power-down and do not issue a convert command while the ADC is powered down.  
After power-on or reset, all bits in ALR Register are cleared to '0'. Reading the register does not clear any bits.  
GPIO Register (Read/Write; see the Digital I/O section)  
The AMC7823 has six general-purpose I/O (GPIO) pins to communicate with external devices. Pins GPIO-4 and  
GPIO-5 are dedicated to general bidirectional, digital I/O signals. The remaining pins (n = 0, 1, 2, 3) are dual-  
purpose and can be programmed as either GPIO pins or ALR (out-of-range) indicators. This register defines the  
status of all GPIO pins and the functions of pins GPIO-0, GPIO-1, GPIO-2 and GPIO-3. The register is formatted  
as shown here.  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
IOMO IOMO IOMO IOMO  
D3 D2 D1 D0  
Bit 9  
Bit 8  
Bit 7  
1
Bit 6  
1
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
1
1
1
1
IOST5 IOST4 IOST3 IOST2 IOST1 IOST0  
IOMOD-n  
Function mode definition bit for pins GPIO-0, GPIO-1, GPIO-2, and GPIO-3 (see Table 8  
and Figure 52)  
IOMOD-n = 0  
Analog input out-of-range detection mode. In this mode, GPIO-n (n = 0, 1, 2, 3) work as  
analog input out-of-range indicators, denoted as output pins ALR-n. The status of each pin  
ALR-n is set by bit ALR-n of the ALR Register. The ALR-n pin is low when the  
corresponding ALR-n bit is '1', and is high-impedance when ALR-n is '0'.  
IOMOD-n = 1  
IOST-n  
GPIO mode. In this mode, pin GPIO-n works as general digital I/O (bidirectional). When  
the pin is output, the status is determined by the corresponding bit IOST-n; it is high-  
impedance for IOST-n = 1, and logic low for IOST-n = 0. When the pin is input, reading  
this bit acquires the digital logic value present at the pin. GPIO data are preserved during  
all power-down conditions.  
I/O STATUS bit of the GPIO-n pin. If the GPIO-n pin works as a general-purpose I/O, this  
bit indicates the actual logic value present at the pin when reading the bit. It also sets the  
state of the corresponding GPIO-n pin (high-impedance for IOST-n = 1, logic low for  
IOST-n = 0) when writing to the bit. An external pull-up resistor is required when using pin  
GPIO-n as an output.  
If the GPIO-n pin works as an analog input out-of-range indicator, then bit IOST-n is a  
complement of the corresponding bit ALR-n in the ALR Register. Writing the IOST-n bit  
does not cause any change. Note that only GPIO-0, GPIO-1, GPIO-2, and GPIO-3 can be  
configured as out-of-range indicators.  
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To avoid loss of alarm information in bits IOST-n during power-down of the ADC, change to direct conversion  
mode (see ADC Control Register) before power-down and do not issue a convert command while the ADC is  
powered down.  
NOTE: When GPIO-n works as a general-purpose I/O pin, bit IOST-n does not change during the power-down  
procedure.  
After power-on or reset, all bits in the GPIO Register are set to '1'. All GPIO pins are configured as general I/O  
pins and are in high-impedance state.  
THRESHOLD REGISTERS  
Threshold-Hi-n and Threshold-Low-n (n = 0, 1, 2, 3) define the upper bound and lower bound of the nth analog  
input range. (See Table 2.) This window determines whether the nth input is out-of-range. When the input is  
outside the window, the corresponding bit ALR-n in the ALR Register is set to '1'.  
For normal operation, the value of Threshold-Hi-n must be greater than the value of Threshold-Low-n; otherwise,  
ALR-n is always set to '1' and an alarm is indicated.  
Threshold-Hi-n Registers (n = 0, 1, 2, 3) (Read/Write)  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
0
0
0
0
THRH THRH THRH THRH THRH THRH THRH THRH THRH THRH THRH THRH  
11 10  
9
8
7
6
5
4
3
2
1
0
Bits [15:12] (READ-  
ONLY)  
'0' when read back. Writing these bits causes no change.  
THRH11–THRH0  
Data bits of the upper bound threshold of the nth analog input. All bits are set to '1'  
after power-on or reset.  
Threshold-Low-n Registers (n = 0, 1, 2, 3) (Read/Write)  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
0
0
0
0
THRL1 THRL1 THRL9 THRL8 THRL7 THRL6 THRL5 THRL4 THRL3 THRL2 THRL1 THRL0  
1
0
Bits [15:12] (READ-  
ONLY)  
Always '0' when read back. Writing these bits causes no change.  
THRL11–THRL0  
Data bits of the lower bound threshold of the nth analog input. This register is  
cleared to '0' after power-on or reset.  
RESET REGISTER (Read/Write)  
The AMC7823 has a special RESET Register that performs the software equivalent function of the device  
RESET pin. To invoke a system reset, write the data word 0xBB3X to this register. Only the upper 12 bits are  
significant; the lowest four bits are Don’t Care.  
Bit 15  
MSB  
Bit 0  
LSB  
Bit 14 Bit 13 Bit 12 Bit 11 Bit 10  
Bit 9  
1
Bit 8  
1
Bit 7  
0
Bit 6  
0
Bit 5  
1
Bit 4  
1
Bit 3  
X
Bit 2  
X
Bit 1  
X
1
0
1
1
1
0
X
X : Don't Care  
Any other value written to this register has no effect. After power-on or reset, this register is cleared to all zeros.  
Therefore, the value 0x0000 is always read back from this register.  
Copyright © 2005–2012, Texas Instruments Incorporated  
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45  
Product Folder Link(s): AMC7823  
AMC7823  
SLAS453F APRIL 2005REVISED MARCH 2012  
www.ti.com  
POWER-DOWN REGISTER (Read/Write)  
NOTE: After power-on or reset, all bits in the Power-Down Register are cleared to '0', and all the components  
controlled by this register are in the powered-down or Off state. To avoid loss of alarm data during power-down  
of the ADC, change the ADC conversion to direct mode (see ADC Control Register) before power-down and do  
not issue a convert command while the ADC is powered down. The Power-Down Register must be set properly  
before operating the ADC, DAC, precision current source, and reference of this device. It is recommended that  
the Power-Down Register be programmed after all other registers have been initialized.  
The Power-Down Register allows the host to manage power dissipation of the AMC7823. When not required, the  
ADC, the precision current source, the reference buffer amplifier or any of the DACs may be put in power-down  
mode to reduce current drain from the supply. Bits in the Power-Down Register control this power-down function.  
Bit  
15  
Bit 0  
LSB  
MSB Bit 14  
Bit 13 Bit 12  
Bit 11  
Bit 10  
Bit 9  
Bit 8  
Bit 7  
Bit 6  
Bit 5  
Bit 4 Bit 3 Bit 2 Bit 1  
PAD PDAC7 PDAC PDAC PDAC4 PDAC PDAC2 PDAC1 PDAC0 PTS PREFB  
X
X
X
X
X
C
6
5
3
X : Don't Care  
PADC  
ADC power-down control bit.  
PADC = '0': The ADC is in power-down mode and ADC conversion is halted.  
PADC = '1': The ADC is in normal operating mode.  
PDAC-n  
DAC-n output buffer amplifier power-down control bit.  
(n = 0, 1, 2, 3, 4, 5, 6, 7)  
PDAC-n = '0': DAC-n output buffer amplifier is in power-down mode. The output pin  
of DAC-n is internally switched from the buffer output to analog ground through an  
internal 5kresistor. Each DAC output buffer may be independently powered down.  
(See the DAC Operation section for details.)  
PDAC-n = '1' and PREFB = '1': DAC-n is in normal operating mode.  
PTS  
Precision current source power-down control bit.  
PTS = '0': Precision current source is in power-down mode and the current output is  
zero.  
PTS = '1': Precision current source is in normal operating mode (see the Precision  
Current Source section for details).  
PREFB  
Reference buffer amplifier power-down control bit. This bit controls the power-down  
condition of the amplifier that supplies a buffered reference voltage to all DAC-n  
resistor strings and to the precision current source. This bit also provides  
configuration information to the precision current source (see the Precision Current  
Source Configuration table, Table 7).  
PREFB = '0': Reference buffer amplifier is in power-down mode. All DACs are  
inoperative. The precision current source may be used only if GREF = '0' (see the  
Precision Current Source Configuration table, Table 7).  
PREFB = '1': Reference buffer amplifier is powered on. This mode is required for  
any DAC-n operation. The precision current source may be used with either value of  
GREF.  
46  
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Copyright © 2005–2012, Texas Instruments Incorporated  
Product Folder Link(s): AMC7823  
AMC7823  
www.ti.com  
SLAS453F APRIL 2005REVISED MARCH 2012  
REVISION HISTORY  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision E (January 2010) to Revision F  
Page  
Changed Level of Pin GALR and DAV, IOH = 0.7mA parameter minimum and maximum specifications in +5V  
Electrical Characteristics table .............................................................................................................................................. 4  
Corrected typo in Digital Input/output, Except Pin GALR and DAV, VOL Logic level (BVDD = 5V) parameter test  
condition in +5V Electrical Characteristics table ................................................................................................................... 4  
Changed Digital Input/output, Except Pin GALR and DAV, VOL Logic level (BVDD = 3V) parameter symbol in +5V  
Electrical Characteristics table .............................................................................................................................................. 4  
Changes from Revision D (August 2008) to Revision E  
Page  
Deleted lead temperature (soldering) rows from Absolute Maximum Ratings table ............................................................ 2  
Copyright © 2005–2012, Texas Instruments Incorporated  
Submit Documentation Feedback  
47  
Product Folder Link(s): AMC7823  
PACKAGE OPTION ADDENDUM  
www.ti.com  
11-Apr-2013  
PACKAGING INFORMATION  
Orderable Device  
AMC7823IRTAR  
AMC7823IRTARG4  
AMC7823IRTAT  
Status Package Type Package Pins Package  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 85  
Top-Side Markings  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4)  
ACTIVE  
WQFN  
WQFN  
WQFN  
WQFN  
RTA  
40  
40  
40  
40  
2000  
Green (RoHS  
& no Sb/Br)  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
AMC7823  
ACTIVE  
ACTIVE  
ACTIVE  
RTA  
RTA  
RTA  
2000  
250  
Green (RoHS  
& no Sb/Br)  
-40 to 85  
AMC7823  
AMC7823  
AMC7823  
Green (RoHS  
& no Sb/Br)  
-40 to 85  
AMC7823IRTATG4  
250  
Green (RoHS  
& no Sb/Br)  
-40 to 85  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability  
information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that  
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between  
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight  
in homogeneous material)  
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4)  
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a  
continuation of the previous line and the two combined represent the entire Top-Side Marking for that device.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
11-Apr-2013  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
20-Mar-2014  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
AMC7823IRTAR  
AMC7823IRTAT  
WQFN  
WQFN  
RTA  
RTA  
40  
40  
2000  
250  
330.0  
180.0  
16.4  
16.4  
6.3  
6.3  
6.3  
6.3  
1.5  
1.5  
12.0  
12.0  
16.0  
16.0  
Q2  
Q2  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
20-Mar-2014  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
AMC7823IRTAR  
AMC7823IRTAT  
WQFN  
WQFN  
RTA  
RTA  
40  
40  
2000  
250  
336.6  
213.0  
336.6  
191.0  
28.6  
55.0  
Pack Materials-Page 2  
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