AD5300BRMZ [ADI]
2.7 V to 5.5 V, 140 muA, Rail-to-Rail Output 8-Bit DAC in a SOT-23; 2.7 V至5.5 V ， 140 MUA ，轨到轨输出8位DAC，采用SOT- 23
| 型号： | AD5300BRMZ |
| 厂家： | 
ADI |
| 描述： | 2.7 V to 5.5 V, 140 muA, Rail-to-Rail Output 8-Bit DAC in a SOT-23 |
| 文件： | 总13页 (文件大小：221K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
2.7 V to 5.5 V, 140 μA, Rail-to-Rail Output
8-Bit DAC in a SOT-23
AD5300
FUNCTIONAL BLOCK DIAGRAM
FEATURES
V
DD
GND
Single 8-Bit DAC
6-Lead SOT-23 and 8-Lead MSOP Packages
Micropower Operation: 140 μA @ 5 V
Power-Down to 200 nA @ 5 V, 50 nA @ 3 V
2.7 V to 5.5 V Power Supply
Guaranteed Monotonic by Design
Reference Derived from Power Supply
Power-On Reset to 0 V
POWER-ON
RESET
AD5300
REF (+) REF (–)
DAC
REGISTER
OUTPUT
BUFFER
8-BIT
DAC
V
OUT
INPUT
CONTROL
LOGIC
POWER-DOWN
CONTROL LOGIC
RESISTOR
NETWORK
3 Power-Down Functions
Low Power Serial Interface with Schmitt-Triggered Inputs
On-Chip Output Buffer Amplifier, Rail-to-Rail Operation
SYNC Interrupt Facility
SYNC SCLK DIN
Qualified for automotive applications
APPLICATIONS
Portable Battery-Powered Instruments
Digital Gain and Offset Adjustment
Programmable Voltage and Current Sources
Programmable Attenuators
GENERAL DESCRIPTION
PRODUCT HIGHLIGHTS
The AD5300 is a single, 8-bit buffered voltage output DAC that
operates from a single 2.7 V to 5.5 V supply, consuming 115 μA
at 3 V. Its on-chip precision output amplifier allows rail-to-rail
output swing to be achieved. The AD5300 uses a versatile 3-wire
serial interface that operates at clock rates up to 30 MHz and is
compatible with standard SPI®, QSPI™, MICROWIRE™, and
DSP interface standards.
The reference for the AD53001 is derived from the power supply
inputs and thus gives the widest dynamic output range. The part
incorporates a power-on reset circuit that ensures that the DAC
output powers up to 0 V and remains there until a valid write takes
place to the device. The part contains a power-down feature that
reduces the current consumption of the device to 200 nA at 5 V
and provides software selectable output loads while in power-
down mode. The part is put into power-down mode over the
serial interface.
1. Available in 6-lead SOT-23 and 8-lead MSOP packages.
2. Low power, single-supply operation. This part operates from a
single 2.7 V to 5.5 V supply and typically consumes 0.35 mW
at 3 V and 0.7 mW at 5 V, making it ideal for battery-powered
applications.
3. The on-chip output buffer amplifier allows the output of
the DAC to swing rail-to-rail with a slew rate of 1 V/μs.
4. Reference derived from the power supply.
5. High speed serial interface with clock speeds up to 30 MHz.
Designed for very low power consumption. The interface
powers up only during a write cycle.
6. Power-down capability. When powered down, the DAC
typically consumes 50 nA at 3 V and 200 nA at 5 V.
The low power consumption of this part in normal operation
makes it ideally suited to portable battery-operated equipment.
The power consumption is 0.7 mW at 5 V, reducing to 1 μW in
power-down mode.
The AD5300 is one of a family of pin-compatible DACs. The
AD5310 is the 10-bit version, and the AD5320 is the 12-bit
version. The AD5300/AD5310/AD5320 are available in 6-lead
SOT-23 packages and 8-lead MSOP packages.
1 Patent pending; protected by U.S. Patent No. 5684481.
Rev. D
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2003–2010 Analog Devices, Inc. All rights reserved.
(VDD = 2.7 V to 5.5 V; RL = 2 k⍀ to GND; CL = 500 pF to GND; all specifications
MIN to TMAX, unless otherwise noted.)
T
AD5300–SPECIFICATIONS
B Version1
Typ
Parameter
Min
Max
Unit
Conditions/Comments
STATIC PERFORMANCE2
Resolution
8
Bits
Relative Accuracy
1
LSB
See Figure 2.
Differential Nonlinearity
Zero-Code Error
Full-Scale Error
0.25
+3.5
–3.5
LSB
LSB
LSB
Guaranteed Monotonic by Design. See Figure 3.
All Zeros Loaded to DAC Register. See Figure 6.
All Ones Loaded to DAC Register. See Figure 6.
+0.5
–0.5
Gain Error
Zero-Code Error Drift
Gain Temperature Coefficient
1.25
% of FSR
µV/°C
ppm of FSR/°C
–20
–5
OUTPUT CHARACTERISTICS3
Output Voltage Range
Output Voltage Settling Time
0
VDD
6
V
µs
4
1/4 Scale to 3/4 Scale Change (40 Hex to C0 Hex).
RL = 2 kΩ; 0 pF < CL < 500 pF. See Figure 16.
Slew Rate
Capacitive Load Stability
1
V/µs
pF
pF
nV-s
nV-s
Ω
470
1000
20
0.5
1
50
20
2.5
5
RL =
RL = 2 kΩ.
∞
.
Digital-to-Analog Glitch Impulse
Digital Feedthrough
DC Output Impedance
Short-Circuit Current
1 LSB Change Around Major Carry. See Figure 19.
mA
mA
µs
VDD = 5 V.
VDD = 3 V.
Power-Up Time
Coming Out of Power-Down Mode. VDD = 5 V.
Coming Out of Power-Down Mode. VDD = 3 V.
µs
LOGIC INPUTS3
Input Current
1
0.8
0.6
µA
V
V
V
V
VINL, Input Low Voltage
VINL, Input Low Voltage
VINH, Input High Voltage
VINH, Input High Voltage
Pin Capacitance
VDD = 5 V.
VDD = 3 V.
VDD = 5 V.
VDD = 3 V.
2.4
2.1
3
pF
POWER REQUIREMENTS
VDD
2.7
5.5
V
IDD (Normal Mode)
VDD = 4.5 V to 5.5 V
VDD = 2.7 V to 3.6 V
IDD (All Power-Down Modes)
VDD = 4.5 V to 5.5 V
VDD = 2.7 V to 3.6 V
DAC Active and Excluding Load Current.
VIH = VDD and VIL = GND.
VIH = VDD and VIL = GND.
140
115
250
200
µA
µA
0.2
0.05
1
1
µA
µA
VIH = VDD and VIL = GND.
VIH = VDD and VIL = GND.
POWER EFFICIENCY
IOUT/IDD
93
%
ILOAD = 2 mA. VDD = 5 V.
NOTES
1Temperature range as follows: B Version: –40°C to +105°C.
2Linearity calculated using a reduced code range of 4 to 251. Output unloaded.
3Guaranteed by design and characterization, not production tested.
Specifications subject to change without notice.
D
REV.
–2–
AD5300
TIMING CHARACTERISTICS1, 2
(VDD = 2.7 V to 5.5 V; all specifications TMIN to TMAX, unless otherwise noted.)
Limit at TMIN, TMAX
VDD = 2.7 V to 3.6 V VDD = 3.6 V to 5.5 V
Parameter
Unit
Conditions/Comments
3
t1
50
13
22.5
13
5
4.5
0
50
33
13
13
13
5
4.5
0
33
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
SCLK Cycle Time
SCLK High Time
SCLK Low Time
SYNC to SCLK Falling Edge Setup Time
Data Setup Time
Data Hold Time
SCLK Falling Edge to SYNC Rising Edge
Minimum SYNC High Time
t2
t3
t4
t5
t6
t7
t8
NOTES
1All input signals are specified with tr = tf = 5 ns (10% to 90% of VDD) and timed from a voltage level of (VIL + VIH)/2.
2See Figure 1.
3Maximum SCLK frequency is 30 MHz at VDD = 3.6 V to 5.5 V and 20 MHz at VDD = 2.7 V to 3.6 V.
Specifications subject to change without notice.
t1
SCLK
t8
t2
t7
t3
t4
SYNC
t6
t5
DB0
DIN
DB15
Figure 1. Serial Write Operation
*Stresses above those listed under Absolute Maximum Ratings may cause perma-
ABSOLUTE MAXIMUM RATINGS*
(TA = 25°C, unless otherwise noted.)
nent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational sections
of this specification is not implied. Exposure to absolute maximum rating condi-
tions for extended periods may affect device reliability.
VDD to GND . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
Digital Input Voltage to GND . . . . . . . –0.3 V to VDD + 0.3 V
VOUT to GND . . . . . . . . . . . . . . . . . . . –0.3 V to VDD + 0.3 V
Operating Temperature Range
Industrial (B Version) . . . . . . . . . . . . . . . –40°C to +105°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C
Junction Temperature (TJ max) . . . . . . . . . . . . . . . . . . . 150°C
SOT-23 Package
Power Dissipation . . . . . . . . . . . . . . . . . . . (TJ max–TA)/θJA
θ
JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . 240°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
MSOP Package
Power Dissipation . . . . . . . . . . . . . . . . . . . (TJ max–TA)/θJA
θ
θ
JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . 206°C/W
JC Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 44°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the AD5300 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
D
REV.
–3–
AD5300
PIN CONFIGURATIONS
MSOP
SOT-23
1
2
3
1
8
7
6
5
V
GND
DIN
6
5
4
SYNC
SCLK
DIN
V
OUT
DD
AD5300
TOP VIEW
(Not to Scale)
2
3
4
GND
NC
NC
AD5300
TOP VIEW
(Not to Scale)
V
SCLK
SYNC
DD
V
OUT
NC = NO CONNECT
PIN FUNCTION DESCRIPTIONS
SOT-23 MSOP
Pin No. Pin No. Mnemonic
Function
1
2
3
4
8
1
VOUT
GND
VDD
Analog Output Voltage from DAC. The output amplifier has rail-to-rail operation.
Ground Reference Point for All Circuitry on the Part.
Power Supply Input. These parts can be operated from 2.5 V to 5.5 V, and VDD should be decoupled
to GND.
4
5
6
7
6
5
DIN
Serial Data Input. This device has a 16-bit shift register. Data is clocked into the register on the
falling edge of the serial clock input.
Serial Clock Input. Data is clocked into the input shift register on the falling edge of the serial
clock input. Data can be transferred at rates up to 30 MHz.
Level Triggered Control Input (Active Low). This is the frame synchronization signal for the
input data. When SYNC goes low, it enables the input shift register and data is transferred in on the
falling edges of the following clocks. The DAC is updated following the 16th clock cycle, unless
SYNC is taken high before this edge, in which case the rising edge of SYNC acts as an interrupt and
the write sequence is ignored by the DAC.
SCLK
SYNC
NC
2, 3
NC
No Connect.
D
REV.
–4–
AD5300
TERMINOLOGY
Gain Error
Relative Accuracy
This is a measure of the span error of the DAC. It is the devia-
tion in slope of the DAC transfer characteristic from ideal
expressed as a percent of the full-scale range.
For the DAC, relative accuracy or integral nonlinearity (INL) is
a measure of the maximum deviation, in LSBs, from a straight line
passing through the endpoints of the DAC transfer function. A
typical INL vs. code plot can be seen in Figure 2.
Total Unadjusted Error
Total unadjusted error (TUE) is a measure of the output error
taking into account all the various errors. A typical TUE vs.
code plot can be seen in Figure 4.
Differential Nonlinearity
Differential nonlinearity (DNL) is the difference between the
measured change and the ideal 1 LSB change between any two
adjacent codes. A specified differential nonlinearity of 1 LSB
maximum ensures monotonicity. This DAC is guaranteed
monotonic by design. A typical DNL vs. code plot can be seen
in Figure 3.
Zero-Code Error Drift
This is a measure of the change in zero-code error with a
change in temperature. It is expressed in µV/°C.
Gain Error Drift
This is a measure of the change in gain error with changes in
temperature. It is expressed in (ppm of full-scale range)/°C.
Zero-Code Error
Zero-code error is a measure of the output error when zero code
(00 Hex) is loaded to the DAC register. Ideally, the output
should be 0 V. The zero-code error is always positive in the
AD5300 because the output of the DAC cannot go below 0 V.
This is due to a combination of the offset errors in the DAC
and output amplifier. Zero-code error is expressed in LSBs. A
plot of zero-code error vs. temperature can be seen in Figure 6.
Digital-to-Analog Glitch Impulse
Digital-to-analog glitch impulse is the impulse injected into the
analog output when the input code in the DAC register changes
state. It is normally specified as the area of the glitch in nV-secs
and is measured when the digital input code is changed by
1 LSB at the major carry transition (7F Hex to 80 Hex). See
Figure 19.
Full-Scale Error
Digital Feedthrough
Full-scale error is a measure of the output error when full-
scale code (FF Hex) is loaded to the DAC register. Ideally,
the output should be VDD – 1 LSB. Full-scale error is expressed
in LSBs. A plot of full-scale error vs. temperature can be
seen in Figure 6.
Digital feedthrough is a measure of the impulse injected into the
analog output of the DAC from the digital inputs of the DAC
but is measured when the DAC output is not updated. It is
specified in nV-secs and is measured with a full-scale code
change on the data bus, i.e., from all 0s to all 1s, and vice versa.
D
REV.
–5–
AD5300–Typical Performance Characteristics
0.5
1.0
0.5
0
1.0
T
= 25؇C
A
0.4
0.3
TUE @ 3V
T
= 25؇C
A
INL @ 3V
0.5
0
0.2
DNL @ 5V
DNL @ 3V
0.1
INL @ 5V
TUE @ 5V
0
–0.1
–0.2
–0.3
–0.4
–0.5
–0.5
–1.0
–0.5
–1.0
T
= 25؇C
A
0
50
100
150
200
250
50
100
150
200
250
0
50
100
150
CODE
200
250
0
CODE
CODE
Figure 3. Typical DNL Plot
Figure 4. Typical Total Unadjusted
Error Plot
Figure 2. Typical INL Plot
3
2
1
2500
1.0
0.5
0
V
= 5V
DD
V
= 5V
DD
V
= 5V
DD
2000
1500
V
= 3V
DD
MAX INL
ZS ERROR
FS ERROR
MAX DNL
0
MIN DNL
MIN INL
1000
500
0
–1
–0.5
–2
–3
–1.0
–40
100 110 120 130 140 150 160 170 180190
50 60 70 80 90
–40
0
40
80
120
0
40
80
120
I
– A
DD
TEMPERATURE – ؇C
TEMPERATURE – ؇C
Figure 7. IDD Histogram with
VDD = 3 V and VDD = 5 V
Figure 6. Zero-Scale Error and
Full-Scale Error vs. Temperature
Figure 5. INL Error and DNL Error
vs. Temperature
5
500
3
T
= 25؇C
A
DAC LOADED WITH FF HEX
4
400
300
200
100
0
DAC LOADED WITH FF HEX
2
3
T
= 25؇C
A
2
1
0
V
V
= 5V
= 3V
DD
1
0
DAC LOADED WITH 00 HEX
DD
DAC LOADED WITH 00 HEX
0
5
10
– mA
15
0
50
100
150
200
250
0
5
10
15
I
CODE
SOURCE/SINK
I
– mA
SOURCE/SINK
Figure 9. Source and Sink Current
Capability with VDD = 5 V
Figure 10. Supply Current vs. Code
Figure 8. Source and Sink Current
Capability with VDD = 3 V
D
REV.
–6–
AD5300
300
250
200
150
100
50
300
250
1.0
0.9
V
= 5V
THREE–STATE
CONDITION
DD
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
200
150
100
50
+105؇C
+25؇C
–40؇C
0
0
2.7
–40
0
40
80
120
3.2
3.7
4.2
– V
4.7
5.2
2.7
3.2
3.7
4.2
– V
4.7
5.2
TEMPERATURE – ؇C
V
DD
V
DD
Figure 11. Supply Current vs.
Temperature
Figure 13. Power-Down Current vs.
Supply Voltage
Figure 12. Supply Current vs.
Supply Voltage
800
600
T
= 25؇C
A
CH 2
CLK
CH 2
CLK
400
200
V
V
OUT
OUT
V
= 5V
V
= 5V
DD
DD
CH 1
HALF-SCALE CODE CHANGE
40 HEX – C0 HEX
FULL-SCALE CODE CHANGE
00 HEX – FF HEX
CH1
V
= 5V
DD
T
= 25؇C
T
= 25؇C
A
A
OUTPUT LOADED WITH
2k⍀ AND 200pF TO GND
OUTPUT LOADED WITH
2k⍀ AND 200pF TO GND
V
= 3V
DD
CH1 1V, CH 2 5V, TIME BASE = 1s/DIV
CH1 1V, CH2 5V, TIME BASE = 1s/DIV
0
0
1
2
3
4
5
V
– V
LOGIC
Figure 14. Supply Current vs. Logic
Input Voltage
Figure 16. Half-Scale Settling Time
Figure 15. Full-Scale Settling Time
2.54
LOADED WITH 2k⍀
AND 200pF TO GND
V
= 5V
2k⍀ LOAD
DD
CH2
TO V
DD
CLK
CODE CHANGE:
80 HEX TO 7F HEX
2.52
2.50
2.48
2.46
V
DD
CH1
CH2
V
OUT
V
OUT
CH1
CH1 1V, CH 2 1V, TIME BASE = 20s/DIV
CH1 1V, CH 2 5V, TIME BASE = 5s/DIV
500ns/DIV
Figure 17. Power-On Reset to 0 V
Figure 19. Digital-to-Analog Glitch
Impulse
Figure 18. Exiting Power-Down
(7F Hex Loaded)
D
REV.
–7–
AD5300
GENERAL DESCRIPTION
D/A Section
Output Amplifier
The AD5300 DAC is fabricated on a CMOS process. The archi-
tecture consists of a string DAC followed by an output buffer
amplifier. Since there is no reference input pin, the power
supply (VDD) acts as the reference. Figure 20 shows a block
diagram of the DAC architecture.
The output buffer amplifier is capable of generating rail-to-rail
voltages on its output, which gives an output range of 0 V to
VDD. It is capable of driving a load of 2 kΩ in parallel with
1000 pF to GND. The source and sink capabilities of the output
amplifier can be seen in Figures 8 and 9. The slew rate is 1 V/µs
with a half-scale settling time of 4 µs with the output loaded.
V
DD
SERIAL INTERFACE
REF (+)
The AD5300 has a 3-wire serial interface (SYNC, SCLK, and
DIN), which is compatible with SPI, QSPI, and MICROWIRE
interface standards as well as most DSPs. See Figure 1 for a
timing diagram of a typical write sequence.
RESISTOR
STRING
DAC REGISTER
V
OUT
REF (–)
OUTPUT
AMPLIFIER
GND
The write sequence begins by bringing the SYNC line low. Data
from the DIN line is clocked into the 16-bit shift register on the
falling edge of SCLK. The serial clock frequency can be as high
as 30 MHz, making the AD5300 compatible with high speed
DSPs. On the 16th falling clock edge, the last data bit is clocked
in and the programmed function is executed (i.e., a change in
DAC register contents and/or a change in the mode of operation).
At this stage, the SYNC line may be kept low or be brought
high. In either case, it must be brought high for a minimum of
33 ns (VDD = 3.6 V to 5.5 V) or 50 ns (VDD = 2.7 V to 3.6 V)
before the next write sequence so that a falling edge of SYNC
can initiate the next write sequence. Since the SYNC buffer
Figure 20. DAC Architecture
Since the input coding to the DAC is straight binary, the ideal
output voltage is given by
D
256
VOUT =VDD
×
where D = decimal equivalent of the binary code that is loaded
to the DAC register; D can range from 0 to 255.
Resistor String
The resistor string section is shown in Figure 21. It is simply a
string of resistors, each of value R. The code loaded to the
DAC register determines at which node on the string the voltage
is tapped off to be fed into the output amplifier. The voltage is
tapped off by closing one of the switches connecting the string
to the amplifier. Because it is a string of resistors, it is guaran-
teed monotonic.
draws more current when VIN = 2.4 V than it does when VIN
=
0.8 V, SYNC should be idled low between write sequences for
even lower power operation of the part. As previously men-
tioned, however, it must be brought high again just before the
next write sequence.
Input Shift Register
The input shift register is 16 bits wide (see Figure 22). The first
two bits are Don’t Cares. The next two are control bits that
control which mode of operation the part is in (normal mode or
any one of three power-down modes). There is a more complete
description of the various modes in the Power-Down Modes
section. The next eight bits are the data bits. These are transferred
to the DAC register on the 16th falling edge of SCLK. Finally, the
last four bits are Don’t Cares.
R
R
TO OUTPUT
AMPLIFIER
R
R
R
Figure 21. Resistor String
DB15 (MSB)
DB0 (LSB)
X
X
PD1
PD 0
D7
D6
D5
D4
D3
D2
D1
D0
X
X
X
X
DATA BITS
0
0
1
1
0
NORMAL OPERATION
1k⍀ TO GND
1
0
1
100k⍀ TO GND
POWER-DOWN MODES
THREE-STATE
Figure 22. Input Register Contents
–8–
D
REV.
AD5300
SCLK
SYNC
DB15
DB0
DB15
DB0
DIN
VALID WRITE SEQUENCE, OUTPUT UPDATES
INVALID WRITE SEQUENCE:
SYNC HIGH BEFORE 16 FALLING EDGE
TH
TH
ON THE 16 FALLING EDGE
Figure 23. SYNC Interrupt Facility
SYNC Interrupt
In a normal write sequence, the SYNC line is kept low for at
least 16 falling edges of SCLK and the DAC is updated on the
16th falling edge. However, if SYNC is brought high before the
16th falling edge, this acts as an interrupt to the write sequence.
The shift register is reset and the write sequence is seen as
invalid; neither an update of the DAC register contents or a
change in the operating mode occurs—see Figure 23.
RESISTOR
AMPLIFIER
STRING DAC
V
OUT
POWER-DOWN
CIRCUITRY
RESISTOR
NETWORK
Power-On Reset
The AD5300 contains a power-on reset circuit that controls the
output voltage during power-up. The DAC register is filled with
zeros and the output voltage is 0 V. It remains there until
a valid write sequence is made to the DAC. This is useful in
applications where it is important to know the state of the out-
put of the DAC while it is in the process of powering up.
Figure 24. Output Stage During Power-Down
The bias generator, the output amplifier, the resistor string, and
other associated linear circuitry are all shut down when the
power-down mode is activated. However, the contents of the
DAC register are unaffected when in power-down. The time to
exit power-down is typically 2.5 µs for VDD = 5 V and 5 µs for
VDD = 3 V (see Figure 18).
Power-Down Modes
The AD5300 contains four separate modes of operation. These
modes are software programmable by setting two bits (DB13
and DB12) in the control register. Table I shows how the state
of the bits corresponds to the mode of operation of the device.
MICROPROCESSOR INTERFACING
AD5300 to ADSP-2101/ADSP-2103 Interface
Figure 25 shows a serial interface between the AD5300 and the
ADSP-2101/ADSP-2103. The ADSP-2101/ADSP-2103 should
be set up to operate in the SPORT transmit alternate framing
mode. The ADSP-2101/ADSP-2103 SPORT is programmed
through the SPORT control register and should be configured
as follows: internal clock operation, active low framing, 16-bit
word length. Transmission is initiated by writing a word to the
Tx register after the SPORT has been enabled.
Table I. Modes of Operation for the AD5300
DB13
DB12
Operating Mode
0
0
Normal Operation
Power-Down Modes
1 kΩ to GND
100 kΩ to GND
Three-State
0
1
1
1
0
1
ADSP-2101/
ADSP-2103*
AD5300*
When both bits are set to 0, the part works normally with its
normal power consumption of 140 µA at 5 V. However, for the
three power-down modes, the supply current falls to 200 nA at
5 V (50 nA at 3 V). Not only does the supply current fall but
the output stage is also internally switched from the output of
the amplifier to a resistor network of known values. This has an
advantage: the output impedance of the part is known while the
part is in power-down mode. There are three different options.
The output is connected internally to GND through a 1 kΩ resis-
tor or a 100 kΩ resistor, or it is left open-circuited (three-stated).
The output stage is illustrated in Figure 24.
SYNC
DIN
TFS
DT
SCLK
SCLK
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 25. AD5300 to ADSP-2101/ADSP-2103 Interface
D
REV.
–9–
AD5300
AD5300 to 68HC11/68L11 Interface
Figure 26 shows a serial interface between the AD5300 and the
68HC11/68L11 microcontroller. SCK of the 68HC11/68L11
drives the SCLK of the AD5300, while the MOSI output drives
the serial data line of the DAC. The SYNC signal is derived
from a port line (PC7). The setup conditions for correct opera-
tion of this interface are as follows: the 68HC11/68L11 should
be configured so that its CPOL bit is a 0 and its CPHA bit is a
1. When data is being transmitted to the DAC, the SYNC line is
taken low (PC7). When the 68HC11/68L11 is configured as
above, data appearing on the MOSI output is valid on the falling
edge of SCK. Serial data from the 68HC11/68L11 is transmit-
ted in 8-bit bytes with only eight falling clock edges occurring in
the transmit cycle. Data is transmitted MSB first. In order to
load data to the AD5300, PC7 is left low after the first eight bits
are transferred, and a second serial write operation is performed
to the DAC and PC7 is taken high at the end of this procedure.
MICROWIRE*
AD5300*
CS
SYNC
SCLK
DIN
SK
SO
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 28. AD5300 to MICROWIRE Interface
APPLICATIONS
Using REF19x as a Power Supply for AD5300
Because the supply current required by the AD5300 is extremely
low, an alternative option is to use a REF19x voltage reference
(REF195 for 5 V or REF193 for 3 V) to supply the required
voltage to the part—see Figure 29. This is especially useful if
your power supply is quite noisy or if the system supply voltages
are at some value other than 5 V or 3 V (e.g., 15 V). The REF19x
will output a steady supply voltage for the AD5300. If the low
dropout REF195 is used, the current it needs to supply to the
AD5300 is 140 µA. This is with no load on the output of the
DAC. When the DAC output is loaded, the REF195 also needs to
supply the current to the load. The total current required (with
a 5 kΩ load on the DAC output) is
68HC11/68L11*
AD5300*
PC7
SYNC
SCLK
DIN
SCK
MOSI
140 µA + (5 V/5 kΩ) = 1.14 mA
*ADDITIONAL PINS OMITTED FOR CLARITY
The load regulation of the REF195 is typically 2 ppm/mA,
which results in an error of 2.3 ppm (11.5 µV) for the 1.14 mA
current drawn from it. This corresponds to a 0.0006 LSB error.
Figure 26. AD5300 to 68HC11/68L11 Interface
AD5300 to 80C51/80L51 Interface
Figure 27 shows a serial interface between the AD5300 and the
80C51/80L51 microcontroller. The setup for the interface is as
follows: TXD of the 80C51/80L51 drives SCLK of the AD5300,
while RXD drives the serial data line of the part. The SYNC
signal is again derived from a bit programmable pin on the port.
In this case, port line P3.3 is used. When data is to be transmitted
to the AD5300, P3.3 is taken low. The 80C51/80L51 transmits
data only in 8-bit bytes; thus, only eight falling clock edges
occur in the transmit cycle. To load data to the DAC, P3.3 is
left low after the first eight bits are transmitted, and a second write
cycle is initiated to transmit the second byte of data. P3.3 is taken
high following the completion of this cycle. The 80C51/80L51
outputs the serial data in a format that has the LSB first. The
AD5300 requires its data with the MSB as the first bit received.
The 80C51/80L51 transmit routine takes this into account.
15V
5V
REF195
140A
SYNC
SCLK
DIN
3-WIRE
SERIAL
INTERFACE
V
= 0V TO 5V
OUT
AD5300
Figure 29. REF195 as Power Supply to AD5300
Bipolar Operation Using the AD5300
The AD5300 has been designed for single-supply operation,
but a bipolar output range is also possible using the circuit in
Figure 30. The circuit in Figure 30 will give an output voltage
range of 5 V. Rail-to-rail operation at the amplifier output is
achievable using an AD820 or an OP295 as the output amplifier.
AD5300*
80C51/80L51*
The output voltage for any input code can be calculated as
P3.3
SYNC
D
256
R1 + R2
R2
R1
TXD
RXD
SCLK
DIN
VO = V
×
×
–VDD ×
DD
R1
where D represents the input code in decimal (0 to 255).
With VDD = 5 V, R1 = R2 = 10 kΩ,
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 27. AD5300 to 80C51/80L51 Interface
10 × D
256
AD5300 to MICROWIRE Interface
VO
=
– 5V
Figure 28 shows an interface between the AD5300 and any
MICROWIRE compatible device. Serial data is shifted out on the
falling edge of the serial clock and is clocked into the AD5300 on
the rising edge of the SK.
This is an output voltage range of 5 V with 00 Hex corresponding
to a –5 V output and FF Hex corresponding to a 5 V output.
D
REV.
–10–
AD5300
R2 = 10k⍀
5V
REGULATOR
0.1F
10F
+5V
POWER
SCLK
+5V
R1 = 10k⍀
V
V
V
DD
AD820/
OP295
؎5V
10k⍀
V
DD
V
V
OUT
DD
SCLK
10F
0.1F
AD5300
–5V
DD
AD5300
10k⍀
3-WIRE
SERIAL
INTERFACE
SYNC
DATA
V
SYNC
OUT
DD
Figure 30. Bipolar Operation with the AD5300
Two 8-Bit AD5300s Together Make One 15-Bit DAC
10k⍀
DIN
GND
By using the configuration in Figure 31, it can be seen that one
15-bit DAC can be made with two 8-bit AD5300s. Because of
the low supply current the AD5300 requires, the output of one
DAC may be directed into the supply pin of the second DAC.
The first DAC has no problem sourcing the required 140 µA
of current for the second DAC.
Figure 32. AD5300 with an Opto-Isolated Interface
Power Supply Bypassing and Grounding
When accuracy is important in a circuit, it is helpful to carefully
consider the power supply and ground return layout on the
board. The printed circuit board containing the AD5300 should
have separate analog and digital sections, each having its own
area of the board. If the AD5300 is in a system where other
devices require an AGND to DGND connection, the connec-
tion should be made at one point only. This ground point should
be as close as possible to the AD5300.
Since the AD5300 works on any supply voltage between 2.5 V
and 5.5 V, the output of the first DAC can be anywhere above
2.5 V. For a VDD of 5 V, this allows the first DAC to use half of
its output range (2.5 V to 5 V), which gives 7-bit resolution on
the output voltage. This output then becomes the supply and
reference for the second DAC. The second DAC has 8-bit reso-
lution on the output range, which gives an overall resolution for
the system of 15 bits.
The power supply to the AD5300 should be bypassed with
10 µF and 0.1 µF capacitors. The capacitors should be physi-
cally as close as possible to the device with the 0.1 µF capacitor
ideally right up against the device. The 10 µF capacitors are the
tantalum bead type. It is important that the 0.1 µF capacitor
has low effective series resistance (ESR) and effective series
inductance (ESI), e.g., common ceramic types of capacitors. This
0.1 µF capacitor provides a low impedance path to ground for
high frequencies caused by transient currents due to internal
logic switching.
A level-shifter is required to ensure that the logic input voltages
do not exceed the supply voltage of the part. The microcontroller
outputs 5 V signals, which need to be level shifted down to 2.5 V
in the case of the second DAC having a supply of only 2.5 V.
5V
V
DD
SYNC
V
= 2.5V TO 5V
OUT
SCLK
AD5300
DIN
The power supply line itself should have as large a trace as pos-
sible to provide a low impedance path and reduce glitch effects
on the supply line. Clocks and other fast switching digital signals
should be shielded from other parts of the board by digital
ground. Avoid crossover of digital and analog signals if possible.
When traces cross on opposite sides of the board, ensure that
they run at right angles to each other to reduce feedthrough
effects through the board. The best board layout technique is
the microstrip technique where the component side of the board
is dedicated to the ground plane only and the signal traces are
placed on the solder side. However, this is not always possible
with a 2-layer board.
MICRO-
CONTROLLER
V
DD
SYNC
LEVEL
SHIFTER
V
= 0V TO 5V
SCLK AD5300
DIN
OUT
15-BIT
RESOLUTION
Figure 31. 15-Bit DAC Using Two AD5300s
Using AD5300 with an Opto-Isolated Interface
In process-control applications in industrial environments, it is
often necessary to use an opto-isolated interface to protect and
isolate the controlling circuitry from any hazardous common-
mode voltages that may occur in the area where the DAC is
functioning. Opto-isolators provide isolation in excess of 3 kV.
Because the AD5300 uses a 3-wire serial logic interface, it
requires only three opto-isolators to provide the required isola-
tion (see Figure 32). The power supply to the part also needs to
be isolated. This is done by using a transformer. On the DAC
side of the transformer, a 5 V regulator provides the 5 V supply
required for the AD5300.
D
REV.
–11–
AD5300
OUTLINE DIMENSIONS
3.00
2.90
2.80
6
1
5
2
4
3
3.00
2.80
2.60
1.70
1.60
1.50
PIN 1
INDICATOR
0.95 BSC
1.90
BSC
1.30
1.15
0.90
0.20 MAX
0.08 MIN
1.45 MAX
0.95 MIN
0.55
0.45
0.35
0.15 MAX
0.05 MIN
10°
4°
0°
SEATING
PLANE
0.60
BSC
0.50 MAX
0.30 MIN
COMPLIANT TO JEDEC STANDARDS MO-178-AB
Figure 33. 6-Lead Small Outline Transistor Package (SOT-23)
(RJ-6)
Dimensions shown in millimeters
3.20
3.00
2.80
8
1
5
4
5.15
4.90
4.65
3.20
3.00
2.80
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.80
0.55
0.40
0.15
0.05
0.23
0.09
6°
0°
0.40
0.25
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 34. 8-Lead Mini Small Outline Package (MSOP)
(RM-8)
Dimensions shown in millimeters
Rev. D | Page 12 of 13
AD5300
ORDERING GUIDE
Model1, 2
Temperature Range
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
Package Description
8-Lead MSOP
8-Lead MSOP
8-Lead MSOP
8-Lead MSOP
6-Lead SOT-23
6-Lead SOT-23
6-Lead SOT-23
6-Lead SOT-23
6-Lead SOT-23
6-Lead SOT-23
6-Lead SOT-23
Package Option
RM-8
RM-8
RM-8
RM-8
RJ-6
RJ-6
RJ-6
RJ-6
RJ-6
Branding
D2B
D2B
D2B
D2B
D2B
D2B
D2B
D2B
AD5300BRM
AD5300BRMZ
AD5300BRMZ-REEL
AD5300BRMZ-REEL7
AD5300BRT-500RL7
AD5300BRT-REEL
AD5300BRT-REEL7
AD5300BRTZ-500RL7
AD5300BRTZ-REEL
AD5300BRTZ-REEL7
AD5300WBRTZ-RL7
D2B
D2B
DG5
RJ-6
RJ-6
1 Z = RoHS Compliant Part.
2 W = Qualified for Automotive Applications.
AUTOMOTIVE PRODUCTS
The AD5300WBRTZ-RL7 model is available with controlled manufacturing to support the quality and reliability requirements of automotive
applications. Note that this automotive model may have specifications that differ from the commercial models; therefore, designers should
review the Specifications section of this data sheet carefully. Only the automotive grade product shown is available for use in automotive
applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific
Automotive Reliability reports for this model.
REVISION HISTORY
12/10—Rev. C to Rev. D
Change to Features Section..............................................................1
Updated Outline Dimensions........................................................12
Moved Ordering Guide; Changes to Ordering Guide................13
Added Automotive Products Section ...........................................13
11/03—Rev. B to Rev. C
Changes to Ordering Guide.............................................................3
Changes to Pin Function Descriptions Section ............................4
Updated Outline Dimensions........................................................12
©2003–2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D00471-0-12/10(D)
Rev. D | Page 13 of 13
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