MAX15500 [MAXIM]
Industrial Analog Current/ Voltage-Output Conditioners; 工业级模拟电流/电压输出调理
| 型号： | MAX15500 |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Industrial Analog Current/ Voltage-Output Conditioners |
| 文件： | 总28页 (文件大小：3367K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-4602; Rev 1; 2/11
Industrial Analog Current/
Voltage-Output Conditioners
General Description
Features
S Supply Voltage Up to Q32.5V
S Output Protected Up to Q35V
The MAX15500/MAX15501 analog output conditioners
provide a programmable current up to Q24mA, or a volt-
age up to Q12V proportional to a control voltage signal.
The control voltage is typically supplied by an external
DAC with an output voltage range of 0 to 4.096V for the
MAX15500 and 0 to 2.5V for the MAX15501. The output
current and voltage are selectable as either unipolar or
bipolar. In the unipolar configuration, a control voltage
of 5% full-scale (FS) produces a nominal output of 0A or
0V to achieve underrange capability. A control voltage
of 100%FS produces one of two programmable levels
(105%FS or 120%FS) to achieve overrange capability.
The outputs of the MAX15500/MAX15501 are protected
against overcurrent conditions and a short to ground or
supply voltages up to Q35V. The devices also monitor for
overtemperature and supply brownout conditions. The
supply brownout threshold is programmable.
S Programmable Output (Plus Overrange)
1ꢀV
ꢀ to 1ꢀV
ꢀ to 5V
2ꢀmꢁ
ꢀ to 2ꢀmꢁ
4 to 2ꢀmꢁ
S Current Output Drives ꢀ to 1kI
S Voltage Output Drives Loads Down to 1kI
S HꢁRT Compliant
S 2ppm Gain Error Drift Over Temperature
S SPI Interface, with Daisy-Chain Capability
S Supports +4.ꢀ96V (MꢁX155ꢀꢀ) or +2.5V
(MꢁX155ꢀ1) Full-Scale Input Signals
S Extensive Error Reporting
Short-Circuit and Overcurrent Protection
Open-Circuit Detection
The MAX15500/MAX15501 are programmed through an
SPIK interface capable of daisy-chained operation. The
MAX15500/MAX15501 provide extensive error reporting
through the SPI interface and an additional open-drain
interrupt output. The devices include an analog output to
monitor load conditions.
Brownout Detection
Overtemperature Protection
S Fast, 4ꢀµs Settling Time
Ordering Information
PꢁRT
PIN-PꢁCKꢁGE
32 TQFN-EP*
32 TQFN-EP*
REFERENCE
MꢁX155ꢀꢀGTJ+
MꢁX155ꢀ1GTJ+
+4.096V
The MAX15500/MAX15501 operate over the -40NC to
+105NC temperature range. The devices are available in
a 32-pin, 5mm x 5mm TQFN package.
+2.5V
Note: All devices are specified over the -40NC to +105NC oper-
ating temperature range.
Applications
Programmable Logic Controllers (PLCs)
Distributed I/Os
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
SPI is a trademark of Motorola, Inc.
Embedded Systems
Industrial Control and Automation
Pin Configuration
TOP VIEW
Simplified Block Diagram
24 23 22 21 20 19 18 17
AVDD
DVDD
AVDDO
16
15
SENSEVP 25
AVDD 26
N.C.
AGND
SCLK
DIN
DOUT
CS1
MAX15500
MAX15501
14 AIN
27
28
29
30
31
32
AGND
AVSS
MON
CS1
SENSERN
SPI
INTERFACE
REFIN
AGND
13
12
BIDIRECTIONAL
SENSERP
COMP
OUT
MAX15500
MAX15501
CURRENT
DRIVER
CS2
READY
AIN
OVER-
CURRENT
11 FSMODE
10 FSSEL
ERROR
HANDLING
PROTECTION
EP*
7
CS2
+
BIDIRECTIONAL
VOLTAGE
9
ERROR
MON
OUTDIS
N.C.
SENSEVP
SENSEVN
ERROR
HANDLING
1
2
3
4
5
6
8
DRIVER
REFIN
AVSS
AVSSO
AGND
DGND
FSMODE
FSSEL
OUTDIS
TQFN
*EXPOSED PAD.
_______________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Industrial Analog Current/
Voltage-Output Conditioners
ꢁBSOLUTE MꢁXIMUM RꢁTINGS
AVDD to AGND .....................................................-0.3V to +35V
AVSS to AGND......................................................-35V to +0.3V
AVDD to AVSS............................................................. 0 to +70V
AVDD to AVDDO........................................................... 0 to +4V
AVSS to AVSSO............................................................ -4V to 0V
DGND to AGND ...................................................-0.3V to +0.3V
AVDD to DVDD.........................................................-6V to +35V
DVDD to DGND....................................................-0.3V to +6.0V
CS1, CS2, SCLK, DIN, DOUT, READY, ERROR, FSMODE,
MON, OUTDIS, FSSEL to DGND......................-0.3V to +6.0V
AIN, REFIN to AGND............................................-0.3V to +6.0V
SENSEVP, SENSEVN, SENSERP,
SENSERN to AGND the higher of -35V and (V
- 0.3V) to
AVSS
the lower of (V
+ 0.3V) and +35V
AVDD
OUT, COMP to AGND.. the higher of -35V and (V
- 0.3V) to
AVSS
the lower of (V
+ 0.3V) and +35V
AVDD
Maximum Current on Pin............................................... 100mA
Continuous Power Dissipation (derate 34.5mW/NC above +70NC)
32-Pin TQFN (T = +70NC, multilayer board).........2758.6mW
A
Operating Temperature Range........................ -40NC to +105NC
Storage Temperature Range............................ -65NC to +150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) ......................................+260NC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
ELECTRICꢁL CHꢁRꢁCTERISTICS
(V
AVDD
= +24V, V
= -24V, V
= 5.0V, C
= 1nF, C
= 0nF, V
= 4.096V for the MAX15500, V = 2.5V for
REFIN
AVSS
DVDD
LOAD
COMP
REFIN
the MAX15501. All specifications for T = -40NC to +105NC. Typical values are at T = +25NC, unless otherwise noted.)
A
A
PꢁRꢁMETER
SYMBOL
CONDITIONS
MIN
TYP
MꢁX
UNITS
POWER SUPPLY (Note 1)
5% overrange (FSMODE = DVDD)
20% overrange (FSMODE = DGND)
5% overrange (FSMODE = DVDD)
20% overrange (FSMODE = DGND)
15
24
24
32.5
32.5
-15
Analog Positive Supply Voltage
V
V
V
V
V
AVDD
18.5
-32.5
-32.5
-24
-24
Analog Negative Supply
Voltage
V
AVSS
-18.5
AVDD to AVDDO Voltage
Difference
V
(Note 1)
(Note 1)
2.5
2.5
AVDDO
AVSS to AVSSO Voltage
Difference
V
AVSSO
Digital Supply Voltage
V
2.7
-7
5.25
7
V
DVDD
Analog Positive Supply Current
Analog Negative Supply Current
Digital Supply Current
I
I
I
= I
+ I , I
= 0A
= 0A
5
mA
mA
mA
AP
AN
AP
AVDD
AVDDO LOAD
I
= I
DVDD
STBYP
+ I
, I
-4.5
0.1
AN
AVSS
AVSSO LOAD
I
V
= 5V
0.4
DVDD
I
= I
+ I
, OUTDIS =
AVDD
AVDDO
Analog Positive Standby Current
Analog Negative Standby Current
I
1
mA
mA
STBYP
DGND or software standby mode
I
= I + I , OUTDIS =
STBYN
AVSS
AVSSO
I
-0.5
STBYN
DGND or software standby mode
ꢁNꢁLOG INPUT (ꢁIN, REFIN)
Input Impedance
R
C
10
10
kI
IN
Input Capacitance
pF
IN
FSSEL = DVDD, MAX15500
FSSEL = DGND, MAX15501
FSSEL = DVDD, MAX15500
FSSEL = DGND, MAX15501
4.0
2.4
4.0
2.4
4.096
2.5
4.2
2.6
4.2
2.6
Analog Input Full Scale
REFIN Full-Scale Input
V
V
V
AIN
4.096
2.5
V
REFIN
2
______________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
ELECTRICꢁL CHꢁRꢁCTERISTICS (continued)
(V
AVDD
= +24V, V
= -24V, V
= 5.0V, C
= 1nF, C
= 0nF, V
= 4.096V for the MAX15500, V = 2.5V for
REFIN
AVSS
DVDD
LOAD
COMP
REFIN
the MAX15501. All specifications for T = -40NC to +105NC. Typical values are at T = +25NC, unless otherwise noted.)
A
A
PꢁRꢁMETER
SYMBOL
CONDITIONS
MIN
TYP
MꢁX
UNITS
CURRENT OUTPUT (Note 2)
V
V
= +24V, V = -24V
750
1000
15
AVDD
AVDD
AVSS
Maximum Load Resistance
R
I
LOAD
= +32.5V, V
= -32.5V
AVSS
Maximum Load Inductance
Maximum Load Capacitance
L
C
= 100nF (Note 3)
= 4.7nF
mH
LOAD
COMP
COMP
C
C
100
FF
LOAD
To 0.1% accuracy,
L
= 20FH,
40
LOAD
C
COMP
= 0nF
To 0.1% accuracy,
L
= 1mH,
500
LOAD
C
COMP
= 0.15nF
Full-scale step
from 0 to 20mA or
-20mA to + 20mA,
To 0.1% accuracy,
L
= 10mH,
= 0.15nF
500
60
LOAD
C
COMP
R
= 750I
LOAD
To 0.01% accuracy,
L
= 20FH,
LOAD
C
COMP
= 0nF
To 0.01% accuracy,
L
C
= 10mH,
= 0.15nF
600
20
LOAD
COMP
Maximum Settling Time
Fs
To 0.1% accuracy,
L
= 20FH,
LOAD
C
COMP
= 0nF
To 0.1% accuracy,
L
= 1mH,
100
LOAD
C
COMP
= 0.15nF
To 0.1% accuracy,
1% full-scale step,
L
LOAD
= 10mH,
= 0.15nF
100
R
LOAD
= 750I
C
COMP
To 0.01% accuracy,
L
= 20FH,
40
LOAD
C
COMP
= 0nF
To 0.01% accuracy,
L
C
= 10mH,
= 0.15nF
200
LOAD
COMP
V
V
= V
= V
Q21
Q24
FSMODE
DVDD
Full-Scale Output Current
I
mA
OUT
FSMODE
DGND
_______________________________________________________________________________________
3
Industrial Analog Current/
Voltage-Output Conditioners
ELECTRICꢁL CHꢁRꢁCTERISTICS (continued)
(V
AVDD
= +24V, V
= -24V, V
= 5.0V, C
= 1nF, C
= 0nF, V
= 4.096V for the MAX15500, V = 2.5V for
REFIN
AVSS
DVDD
LOAD
COMP
REFIN
the MAX15501. All specifications for T = -40NC to +105NC. Typical values are at T = +25NC, unless otherwise noted.)
A
A
PꢁRꢁMETER
Offset Error
SYMBOL
CONDITIONS
= 5% of V (unipolar mode),
MIN
TYP
Q0.1
Q5
MꢁX
UNITS
%FS
V
V
AIN
REFIN
Q0.5
= 50% of V
(bipolar mode)
AIN
REFIN
Offset-Error Drift
ppm/NC
0.01% precision
, tested
according to the
ideal transfer
functions shown in
Table 8
R
MAX15500
MAX15501
Q0.1
Q0.1
Q0.51
Q0.5
SENSE
Gain Error
GE
%FS
Gain-Error Drift
No R
drift
Q2
ppm/NC
SENSE
Integral Nonlinearity Error
INL
0.05
%FS
(dI
/dV
), I
= 24mA, R
=
OUT
OUT OUT
LOAD
Output Conductance
750Ito 0I, FSMODE = DGND, unipolar
mode
1.0
1.6
FA/V
At DC, V
= +24V to +32.5V, V
AVSS
AVDD
Power-Supply Rejection Ratio
PSRR
= -24V to -32.5V, V
= V , unipolar
REFIN
FA/V
AIN
mode, FSMODE = DVDD
Overcurrent Limit
R
shorted
25
30
20
40
mA
SENSE
0.1Hz to 10Hz
At 1kHz
nA
RMS
Output Current Noise
2.6
1.5
30
nA/√Hz
mA/Fs
kHz
Output Slew Rate
Small-Signal Bandwidth
Maximum OUT Voltage to
AVDDO
V
V
- V
2.0
2.0
V
V
AVDDO
OUT
Minimum OUT Voltage to
AVSSO
- V
OUT
AVSSO
VOLTꢁGE OUTPUT (R
= 1kI)
LOꢁD
Minimum Resistive Load
Maximum Capacitive Load
R
C
1
kI
FF
LOAD
C
COMP
= 4.7nF
100
LOAD
To 0.1% accuracy, load = 1kIin parallel
with 1nF, C = 0nF
20
1000
30
COMP
To 0.1% accuracy, load = 1kIin parallel
with 1FF, C = 4.7nF
COMP
Maximum Settling Time (Full-
Scale Step)
Fs
To 0.01% accuracy, load = 1kIin parallel
with 1nF, C = 0nF
COMP
To 0.01% accuracy, load = 1kIin parallel
with 1FF, C = 4.7nF
1300
COMP
4
______________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
ELECTRICꢁL CHꢁRꢁCTERISTICS (continued)
(V
AVDD
= +24V, V
= -24V, V
= 5.0V, C
= 1nF, C
= 0nF, V
= 4.096V for the MAX15500, V = 2.5V for
REFIN
AVSS
DVDD
LOAD
COMP
REFIN
the MAX15501. All specifications for T = -40NC to +105NC. Typical values are at T = +25NC, unless otherwise noted.)
A
A
PꢁRꢁMETER
SYMBOL
CONDITIONS
To 0.1% accuracy, load = 1kIin parallel
with 1nF, C = 0nF
MIN
TYP
MꢁX
UNITS
10
COMP
To 0.1% accuracy, load = 1kIin parallel
with 1FF, C = 4.7nF
300
20
COMP
Maximum Settling Time
(1% Full-Scale Step)
Fs
To 0.01% accuracy, load = 1kIin parallel
with 1nF, C = 0nF
COMP
To 0.01% accuracy, load = 1kIin parallel
with 1FF, C = 4.7nF
600
Q0.1
COMP
Tested according to the ideal transfer
functions shown in Table 9
Gain Error
Q0.5
Q0.5
45
%FS
Gain-Error Drift
Q2
ppm/NC
5V range
FSMODE = DVDD
5.25
10V range
10.5
6
Full-Scale Output Voltage
V
V
OUT
5V range
FSMODE = DGND
10V range
12
V
V
= 5% of V
= 50% of V
(unipolar mode),
AIN
AIN
REFIN
Offset Error
Q0.1
%FS
(bipolar mode)
REFIN
Offset-Error Drift
Q2
ppm/NC
Integral Nonlinearity Error
INL
0.05
%FS
At DC, V
= +18.5V to +32.5V, V
AVSS
AVDD
Power-Supply Rejection
Output-Voltage Noise
PSRR
30
FV/V
= -18.5V to -32.5V, V
0.1Hz to 10Hz
1kHz
= V
REFIN
AIN
16.3
250
1.5
FV
RMS
nV/√Hz
V/Fs
Output-Voltage Slew Rate
Short-Circuit Current
20
30
mA
Maximum OUT Voltage to
AVDDO
V
V
- V
2.0
2.0
V
V
AVDDO
OUT
Minimum OUT Voltage to
AVSSO
- V
OUT
AVSSO
_______________________________________________________________________________________
5
Industrial Analog Current/
Voltage-Output Conditioners
ELECTRICꢁL CHꢁRꢁCTERISTICS (continued)
(V
AVDD
= +24V, V
= -24V, V
= 5.0V, C
= 1nF, C
= 0nF, V
= 4.096V for the MAX15500, V = 2.5V for
REFIN
AVSS
DVDD
LOAD
COMP
REFIN
the MAX15501. All specifications for T = -40NC to +105NC. Typical values are at T = +25NC, unless otherwise noted.)
A
A
PꢁRꢁMETER
SYMBOL
CONDITIONS
MIN
TYP
MꢁX
UNITS
OUTPUT MONITOR (MON)
Current mode, see the Output Monitor
section for V equations
3
MON
Maximum Output Voltage
Output Resistance
V
Voltage mode, see the Output Monitor
section for V equations
3
MON
35
kI
OVERTEMPERꢁTURE DETECTION
Overtemperature Threshold
+150
10
NC
NC
Overtemperature Threshold
Hysteresis
DIGITꢁL INPUTS (CS1, CS2, SCLK, DIN, OUTDIS, FSSEL, FSMODE)
0.7 x
Input High Voltage
Input Low Voltage
V
V
V
IH
V
DVDD
0.3 x
V
IL
V
DVDD
Input Hysteresis
V
300
Q0.1
10
mV
FA
pF
IHYST
Input Leakage Current
Input Capacitance
I
V
= 0V or V
DVDD
Q1.0
IN
INPUT
C
IN
DIGITꢁL OUTPUT (DOUT, READY)
Output Low Voltage
V
I
I
= 4mA
0.4
V
V
OL
OH
OZ
SINK
V
-
DVDD
0.5
Output High Voltage
V
= 4mA
SOURCE
Output Three-State Leakage
Output Three-State Capacitance
Output Short-Circuit Current
I
DOUT only
DOUT only
Q0.1
15
Q10
FA
pF
C
OZ
I
V
= 5.25V
Q150
mA
OSS
DVDD
DIGITꢁL INTERRUPT (ERROR)
Interrupt Active Voltage
V
INT
I
= 5.0mA
0.4
V
SINK
Interrupt Inactive Leakage
Interrupt Inactive Capacitance
Interrupt Short-Circuit Current
I
Q0.1
15
Q1.0
FA
pF
mA
INTZ
C
INTZ
I
V
= 2.7V
5
30
INTSS
DVDD
6
______________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
ELECTRICꢁL CHꢁRꢁCTERISTICS (continued)
(V
AVDD
= +24V, V
= -24V, V
= 5.0V, C
= 1nF, C
= 0nF, V
= 4.096V for the MAX15500, V = 2.5V for
REFIN
AVSS
DVDD
LOAD
COMP
REFIN
the MAX15501. All specifications for T = -40NC to +105NC. Typical values are at T = +25NC, unless otherwise noted.)
A
A
PꢁRꢁMETER
TIMING CHꢁRꢁCTERISTICS
Serial-Clock Frequency
SCLK Pulse-Width High
SCLK Pulse-Width Low
SYMBOL
CONDITIONS
MIN
TYP
MꢁX
UNITS
f
(Note 4)
0
20
20
15
0
20
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
SCLK
t
40% duty cycle
60% duty cycle
To 1st SCLK falling edge
(Note 5)
CH
t
CL
t
CS_ Fall to SCLK Fall Setup Time
SCLK Fall to CS_ Fall Hold Time
DIN to SCLK Fall Setup Time
DIN to SCLK Fall Hold Time
SCLK Fall to DOUT Settle Time
SCLK Fall to DOUT Hold Time
SCLK Fall to DOUT Disable
CSS
CSH
t
t
15
0
DS
t
DH
t
C
C
= 20pF
= 0pF
30
DOT
LOAD
t
2
DOH
LOAD
t
14th SCLK deassertion (Note 6)
30
30
35
35
35
DOZ
t
16th SCLK assertion, C
= 0pF or 20pF
2
1
SCLK Fall to READY Fall
CS_ Fall to DOUT Enable
CS_ Rise to DOUT Disable
CS_ Rise to READY Rise
CS_ Pulse-Width High
CR
LOAD
t
Asynchronous assertion
Asynchronous deassertion
Asynchronous deassertion, C
DOE
t
CSDOZ
t
= 20pF
LOAD
CSR
t
15
CSW
Note 1: Use diodes as shown in the Typical Operating Circuit/Functional Diagram to ensure a voltage difference of 2V to 3.5V
from AVDD to AVDDO and from AVSS to AVSSO.
Note 2: R
= 750I. For the MAX15500, R
= 48.7I for FSMODE = DVDD and R
= 42.2I for FSMODE = DGND.
LOAD
SENSE
SENSE
= 41.2I for FSMODE = DGND. See the Typical
SENSE
For the MAX15501, R
Operating Circuit/Functional Diagram.
= 47.3I for FSMODE = DVDD and R
SENSE
Note 3: Condition at which part is stable.
Note 4: The maximum clock speed for daisy-chain applications is 10MHz.
Note 5: t
is applied to CS_ falling to determine the 1st SCLK falling edge in a free-running SCLK application. It is also applied
CSH
to CS_ rising with respect to the 15th SCLK falling edge to determine the end of the frame.
Note 6: After the 14th SCLK falling edge, the MAX15500/MAX15501 outputs are high impedance and DOUT data is ignored.
_______________________________________________________________________________________
7
Industrial Analog Current/
Voltage-Output Conditioners
Typical Operating Characteristics
(V
AVDD
= +24V, V
= +5V, V
= -24V, C
= 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output
DVDD
AVSS
LOAD
mode, V
= +4.096V, T = +25NC, unless otherwise specified.)
A
REFIN
VOLTAGE-MODE OUTPUT SLEW
RATE vs. TEMPERATURE
CURRENT-MODE OUTPUT SLEW
RATE vs. TEMPERATURE
SUPPLY CURRENT vs. TEMPERATURE
10
8
3.0
2.5
2.0
1.5
1.0
0.5
0
3.0
2.5
2.0
1.5
1.0
0.5
0
R
C
= 750I
= 1FF
NO LOAD
LOAD
LOAD
NO LOAD
6
4
2
I
AVDD
0
-2
-4
-6
-8
10
I
AVSS
-40 -25 -10
5
20 35 50 65 80 95 105
-40 -25 -10
5
20 35 50 65 80 95 105
-40 -25 -10
5
20 35 50 65 80 95 105
TEMPERATURE (NC)
TEMPERATURE (NC)
TEMPERATURE (NC)
VOLTAGE-MODE OUTPUT NOISE
vs. FREQUENCY
CURRENT-MODE OUTPUT NOISE
vs. FREQUENCY
1000
900
800
700
600
500
400
300
200
100
0
1000
900
800
700
600
500
400
300
200
100
0
V
= 0V
V
= 200mV
AIN
AIN
UNIPOLAR
UNIPOLAR
VOLTAGE
MODE (0 to 5V)
CURRENT MODE
(0 to 20mA)
10
100
1k
10k
10
100
1k
10k
FREQUENCY (Hz)
FREQUENCY (Hz)
VOLTAGE-MODE PSRR
vs. SUPPLY VOLTAGE
DIGITAL FEEDTHROUGH
MAX15500 toc06
100
90
80
70
60
50
40
30
20
10
0
V
= 4.096V
AIN
SCLK
2V/div
V
OUT
(AC-COUPLED)
1mV/div
SCLK = DIN
SCLK = 1MHz
CS_ = HIGH
V
= 0.5 x V
AIN
REFIN
24
26
28
30
32
400ns/div
SUPPLY VOLTAGE (V)
8
______________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
Typical Operating Characteristics (continued)
(V
AVDD
= +24V, V
= +5V, V
= -24V, C
= 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output
DVDD
AVSS
LOAD
mode, V
= +4.096V, T = +25NC, unless otherwise specified.)
REFIN
A
CURRENT-MODE PSRR vs.
SUPPLY VOLTAGE
LOAD TRANSIENT (VOLTAGE MODE)
MAX15500 toc09
1.0
0.9
0.8
0.7
0.6
I
OUT
10mA/div
OmA
V
OUT (AC-COUPLED)
20mV/div
0.5
0.4
0.3
0.2
0.1
0
24 25 26 27 28 29 30 31 32
SUPPLY VOLTAGE (V)
40Fs/div
FULL-SCALE OUTPUT VOLTAGE
vs. TEMPERATURE
LOAD TRANSIENT (CURRENT MODE)
MAX15500 toc10
20
16
12
8
V
= 4.096V
AIN
V
OUT
10V/div
O
4
I
OUT
0
10mA/div
-4
-8
0mA
-12
-16
-20
40Fs/div
-40 -25 -10
5
20 35 50 65 80 95
TEMPERATURE (NC)
OUTPUT CURRENT DRIFT
vs. TEMPERATURE
STANDBY SUPPLY CURRENT
vs. TEMPERATURE
10
6
2.0
1.5
V
= 4.096V
AIN
NO LOAD
1.0
I
0.5
AVDD
2
0
-2
-6
-10
-0.5
-1.0
-1.5
-2.0
I
AVSS
-40 -25 -10
5
20 35 50 65 80 95
-40 -25 -10
5
20 35 50 65 80 95
TEMPERATURE (NC)
TEMPERATURE (NC)
_______________________________________________________________________________________
9
Industrial Analog Current/
Voltage-Output Conditioners
Typical Operating Characteristics (continued)
(V
AVDD
= +24V, V
= +5V, V
= -24V, C
= 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output
DVDD
AVSS
LOAD
mode, V
= +4.096V, T = +25NC, unless otherwise specified.)
A
REFIN
GAIN vs. FREQUENCY
(HART COMPLIANT)
WAKEUP FROM STANDBY
(VOLTAGE MODE)
WAKEUP FROM STANDBY
(CURRENT MODE)
MAX15500 toc14
MAX15500 toc15
0
-4
BIPOLAR
CURRENT MODE
OUTDIS
2V/div
2V/div
OUTDIS
-8
0V
-12
-16
-20
5V/div
V
OUT
I
OUT
UNIPOLAR
CURRENT MODE
10mA/div
0V
FULL-SCALE INPUT
BIPOLAR VOLTAGE MODE
5% OVERRANGE
V
= 40mV
P-P
AIN
10
100
1k
FREQUENCY (Hz)
10k
100k
40Fs/div
50Fs/div
SMALL-SIGNAL STEP RESPONSE
SMALL-SIGNAL STEP RESPONSE
(VOLTAGE MODE)
OUTPUT SHORT-CIRCUIT CURRENT
vs. TEMPERATURE
(CURRENT MODE)
MAX15500 toc17
MAX15500 toc18
35.0
34.5
34.0
33.5
33.0
32.5
32.0
31.5
31.0
30.5
30.0
V
= 4.096V
AIN
V
AIN
(AC-COUPLED)
50mV/div
V
AIN
20mV/div
V
OUT
I
OUT
(AC-COUPLED)
100mV/div
100FA/div
5Fs/div
1Fs/div
-40 -25 -10
5
20 35 50 65 80 95
TEMPERATURE (NC)
VOLTAGE-MODE MON TRANSFER
CURVE vs. OUTPUT CURRENT
CURRENT-MODE MON TRANSFER
CURVE vs. OUTPUT VOLTAGE
VOLTAGE-MODE MAXIMUM OUT TO
AVDDO VOLTAGE vs. TEMPERATURE
3.0
2.6
2.2
1.8
1.4
1.0
3.0
2.8
2.6
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
V
AIN
= 4.096V
V
= 4.096V
AIN
V
= 4.096V
AIN
NO LOAD ON MON
NO LOAD ON MON
0
1
2
3
4
5
6
7
8
9
10 11
0
4
8
12
16
-40 -25 -10
5
20 35 50 65 80 95
I
(mA)
V
(V)
OUT
TEMPERATURE (NC)
OUT
1ꢀ _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
Typical Operating Characteristics (continued)
(V
AVDD
= +24V, V
= +5V, V
= -24V, C
= 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output
DVDD
AVSS
LOAD
mode, V
= +4.096V, T = +25NC, unless otherwise specified.)
A
REFIN
LARGE-SIGNAL SETTLING TIME
(VOLTAGE MODE, RISING EDGE)
CURRENT-MODE OUTPUT
CONDUCTANCE vs. OUTPUT VOLTAGE
LARGE-SIGNAL SETTLING TIME
(VOLTAGE MODE, FALLING EDGE)
MAX15500 toc24
MAX15500 toc25
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
R = 1kI
R = 1kI
L
L
V
AIN
5V/div
C = 1nF, C
= 0nF
L
COMP
V
AIN
V
OUT
5V/div
5V/div
C = 47nF, C
= 0nF
L
COMP
C = 470nF, C
= 4.7nF
L
COMP
0
C = 470nF, C
L
= 4.7nF
COMP
C = 47nF, C
L
= 0nF
COMP
V
OUT
5V/div
C = 1nF, C
L
= 0nF
COMP
100Fs/div
0
2
4
6
8
10 12 14 16
100Fs/div
OUTPUT VOLTAGE (V)
LARGE-SIGNAL SETTLING TIME
(VOLTAGE MODE, RISING EDGE)
LARGE-SIGNAL SETTLING TIME
(VOLTAGE MODE, RISING EDGE)
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, RISING EDGE)
MAX15500 toc26
MAX15500 toc27
MAX15500 toc28
R = 1kI
L
R = 1kI
L
R = 750I
L
V
V
V
AIN
5V/div
AIN
AIN
L = 22FH, C = 0nF
L COMP
C = 1FF, C
= 4.7nF
5V/div
5V/div
L
COMP
C = 10FF,
L
C = 100FF,
L
C
= 4.7nF
COMP
C
= 4.7nF
COMP
L = 220FH, C
= 0nF
L
COMP
V
OUT
V
OUT
L = 1mH, C
L
= 1nF
5V/div
COMP
C = 100FF,
L
C = 10FF,
L
C
= 4.7nF
COMP
C
= 4.7nF
COMP
C = 1FF, C
= 4.7nF
L
COMP
I
OUT
4mA/div
10ms/div
10ms/div
200Fs/div
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, FALLING EDGE)
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, RISING EDGE)
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, FALLING EDGE)
MAX15500 toc29
MAX15500 toc30
MAX15500 toc31
R = 750I
L
R = 20I
L
R = 20I
L
V
V
AIN
5V/div
AIN
V
AIN
L = 22FH, C
= 0.15nF
5V/div
L
COMP
L = 22FH, C
= 0nF
L
COMP
L = 220FH,
L
L = 220FH, C
L
= 0nF
COMP
C
= 0.47nF
COMP
L = 1mH, C
= 1nF
L
COMP
L = 1mH, C
= 1nF
L
COMP
L = 1mH, C
L
= 1nF
COMP
L = 220FH,
L
I
C
= 0.47nF
OUT
COMP
I
I
OUT
OUT
4mA/div
4mA/div
4mA/div
L = 22FH, C
= 0.15nF
L
COMP
200Fs/div
20Fs/div
20Fs/div
______________________________________________________________________________________ 11
Industrial Analog Current/
Voltage-Output Conditioners
Typical Operating Characteristics (continued)
(V
AVDD
= +24V, V
= +5V, V
= -24V, C
= 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output
DVDD
AVSS
LOAD
mode, V
= +4.096V, T = +25NC, unless otherwise specified.)
A
REFIN
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, RISING EDGE)
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, RISING EDGE)
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, FALLING EDGE)
MAX15500 toc32
MAX15500 toc34
MAX15500 toc33
R = 750I
L
R = 20I
L
R = 750I
L
L = 10mH, C
= 10nF
L
COMP
V
AIN
V
V
AIN
5V/div
AIN
5V/div
5V/div
L = 50mH, C
= 100nF
= 470nF
L
COMP
L = 80mH, C
= 470nF
L = 50mH, C
L
= 100nF
L
COMP
COMP
L = 80mH, C
L
COMP
L = 50mH, C
= 100nF
L
COMP
L = 80mH,
L
L = 10mH, C
= 10nF
L
COMP
C
= 470nF
COMP
I
L = 10mH, C
= 10nF
OUT
L
COMP
I
OUT
4mA/div
4mA/div
I
OUT
4mA/div
100ms/div
10ms/div
100ms/div
LARGE-SIGNAL SETTLING TIME
(CURRENT MODE, FALLING EDGE)
CURRENT-MODE INL
VOLTAGE-MODE INL
MAX15500 toc35
0.04
0.03
0.02
0.01
0
0.04
0.03
0.02
0.01
0
R = 20I
L
V
AIN
20V/div
L = 80mH, C
= 470nF
L
COMP
L = 50mH, C
= 100nF
= 10nF
L
COMP
L = 10mH, C
L
COMP
-0.01
-0.02
-0.03
-0.04
-0.01
-0.02
-0.03
-0.04
I
OUT
4mA/div
10ms/div
0
0.6 1.2 1.8 2.4 3.0 3.6 4.2
0
0.6 1.2 1.8 2.4 3.0 3.6 4.2
(V)
V
(V)
V
AIN
AIN
CURRENT-MODE
OPEN-CIRCUIT DETECTION
VOLTAGE-MODE
SHORT-CIRCUIT DETECTION
MAX15500 toc39
MAX15500 toc38
I
50mA/div
OUT
50mA/div
2V/div
0mA
I
OUT
0mA
ERROR
ERROR
2V/div
100ms/div
100ms/div
12 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
Pin Description
PIN
1
NAME
SCLK
DIN
FUNCTION
SPI Clock Input. Activate SCLK only when CS_ is low to minimize noise coupling.
SPI Data Input. Data is clocked into the serial interface on the falling edge of SCLK.
2
SPI Data Output. Data transitions at DOUT on the falling edge of SCLK. DOUT is high impedance
when either CS1 or CS2 is high.
3
4
DOUT
Active-Low Device Ready Output. READY is an active-low output that goes low when the device
successfully completes processing an SPI data frame. READY returns high at the next rising edge
of CS_. In daisy-chain applications, the READY output typically drives the CS_ input of the next
device in the chain or a GPIO of a microcontroller.
READY
Active-Low Flag Output. ERROR is an open-drain output that pulls low when output short circuit,
output open circuit, overtemperature, or brownout conditions occur. ERROR typically drives an
interrupt input of a microcontroller. The ERROR output is cleared after the internal error register is
read through the SPI interface. Connect a 10kΩ pullup resistor from ERROR to DVDD.
5
ERROR
Digital Power-Supply Voltage Input. Apply either a 3V or 5V nominal voltage supply to DVDD.
DVDD powers the digital portion of the MAX15500/MAX15501. Bypass DVDD to DGND with a 0.1FF
capacitor as close as possible to the device.
6
7
DVDD
DGND
N.C.
Digital Ground
8, 16,
24, 32
No Connection. Not internally connected.
Active-Low Output Disable Input. OUTDIS is an active-low logic input that forces the analog output
to 0A or 0V and puts the device in standby mode when connected to DGND. Connect OUTDIS to
DVDD for normal operation.
9
OUTDIS
Full-Scale Select Input. Connect FSSEL to DVDD for the MAX15500 when applying a +4.096V
reference at REFIN. Connect FSSEL to DGND for the MAX15501 when applying a +2.50V reference
at REFIN.
10
FSSEL
Overrange Mode Select Input. Connect FSMODE to DVDD to set the output voltage to 105%FS
when the input voltage is equal to the full-scale value. Connect FSMODE to DGND to set the output
voltage to 120%FS when the input voltage is equal to the full-scale value. FSMODE has no effect in
current mode.
11
FSMODE
12, 15, 27
13
AGND
REFIN
Analog Ground
Reference Voltage Input. Connect REFIN to an external +4.096V reference for the MAX15500 or
+2.5V reference for the MAX15501. REFIN is used to set the offset for unipolar and bipolar modes.
Analog Signal Input. The analog input signal range at AIN is from 0V to the nominal full scale of
+4.096V for the MAX15500 and +2.5V for the MAX15501.
14
17
18
AIN
Negative Output Driver Supply Voltage Input. AVSSO provides power to the driver output stage.
Bypass AVSSO to AVSS with a 0.1FF capacitor. Use diodes as shown in the Typical Operating
Circuit/Functional Diagram to ensure a voltage difference of 2V to 3.5V between AVSS and AVSSO.
AVSSO
COMP
Output Amplifier Compensation Feedback Node. Connect a compensation capacitor from COMP to
OUT. See Table 10 for the recommended compensation capacitor values.
______________________________________________________________________________________ 13
Industrial Analog Current/
Voltage-Output Conditioners
Pin Description (continued)
PIN
NAME
FUNCTION
Analog Output. The analog voltage or current output range at OUT is programmable. See Tables
1 to 4 for possible output range settings.
19
OUT
Positive Output Driver Supply Voltage Input. AVDDO provides power to the driver output stage.
Bypass AVDDO to AVDD with a 0.1FF capacitor. Use diodes as shown in the Typical Operating
Circuit/Functional Diagram to ensure a voltage difference of 2V to 3.5V between AVDD and
AVDDO.
20
AVDDO
Sense Resistor Positive Connection. See the Typical Operating Circuit/Functional Diagram for the
typical connection.
21
22
23
25
SENSERP
SENSERN
SENSEVN
SENSEVP
Sense Resistor Negative Connection. See the Typical Operating Circuit/Functional Diagram for the
typical connection.
Kelvin Sense Voltage Negative Input. See the Typical Operating Circuit/Functional Diagram for the
typical connection.
Kelvin Sense Voltage Positive Input. See the Typical Operating Circuit/Functional Diagram for the
typical connection.
26
28
29
30
31
AVDD
AVSS
MON
CS1
Positive Analog Supply Voltage Input. Bypass AVDD to AGND with a 0.1FF capacitor.
Negative Analog Supply Voltage Input. Bypass AVSS to AGND with a 0.1FF capacitor.
Load Monitoring Output. MON provides an analog 0 to 3V output. See the Output Monitor section.
Active-Low SPI Chip-Select Input 1. See the SPI Interface section.
Active-Low SPI Chip-Select Input 2. See the SPI Interface section.
CS2
Exposed Pad. Internally connected to AVSS. Connect to AVSS. Connect to a large copper area to
maximize thermal performance. Do not connect ground or signal lines through EP.
—
EP
14 _____________________________________________________________________________________
Typical Operating Circuit/Functional Diagram
24V
5V
0.1FF
0.1FF
0.1FF
DVDD
AVDD
AVDDO
10kI
AIN
DAC
SENSEVP
CABLE1
SENSERP
COMP
PGA
C
COMP
R
SENSE
OUT
CABLE2
CABLE3
10kI
REFIN
2.5V/4.096V
REF
SENSERN
R
LOAD
C
LOAD
SENSEVN
OFFSET
GENERATOR
OUTPUT STAGE
DIN
SCLK
CS1
CS2
DOUT
DVDD
POR
WRITE
SCLK
MON
SPI INTERFACE/
LOGIC I/O
BROWNOUT
ADC
CS
TEMP
MONITOR
FC
MAX15500
MAX15501
READ
AGND
DGND
0.1FF
AVSSO
AVSS
ERROR
INT
READY
GPIO
DVDD
0.1FF
-24V
*FSSEL IS CONNECTED TO DGND FOR THE MAX15501.
Industrial Analog Current/
Voltage-Output Conditioners
device applications. The MAX15500/MAX15501 provide
Detailed Description
extensive error reporting of short-circuit, open-circuit,
brownout, and overtemperature conditions through the
SPI interface and an additional open-drain interrupt
output (ERROR). The MAX15500/MAX15501 include an
analog 0 to 3V output (MON) to monitor the load condi-
tion at OUT.
The MAX15500/MAX15501 output a programmable cur-
rent up to Q24mA or a voltage up to Q12V proportional to
a control signal at AIN. The devices operate from a dual
15V to 32.5V supply. The control voltage applied at AIN
is typically supplied by an external DAC with an output
voltage range of 0 to 4.096V for the MAX15500 and 0
to 2.5V for the MAX15501. The MAX15500/MAX15501
are capable of both unipolar and bipolar current and
voltage outputs. In current mode, the devices produce
currents of -1.2mA to +24mA or -24mA to +24mA. In
voltage mode, the devices produce voltages of -0.3V
to +6V, -0.6V to +12V, or Q12V. To allow for overrange
and underrange capability in unipolar mode, the transfer
function of the MAX15500/MAX15501 is offset such that
Analog Section
The MAX15500/MAX15501 support two output modes:
current and voltage. Each mode has different full-scale
output values depending on the state of FSMODE as
detailed in Tables 1 to 4 and Figures 1 and 2. Use the
device configuration register in Table 6 to select the
desired voltage or current output range.
Startup
During startup, the MAX15500/MAX15501 output is set
to zero and all register bits are set to zero. The devices
remain in standby mode until they are configured
through the SPI interface.
when the voltage at AIN is 5% of full scale, I
is 0mA
OUT
and V
is 0V. Once V
attains full scale, V
or
OUT
AIN
OUT
I
becomes full scale +5% or +20% depending on
OUT
the state of FSMODE. The MAX15500/MAX15501 are
protected against overcurrent and short-circuit condi-
tions when OUT goes to ground or a voltage up to
Q32.5V. The devices also monitor for overtemperature
and supply brownout conditions. The supply brownout
threshold is programmable between 10V and 24V in
2V increments.
Input Voltage Range
The input voltage full-scale level is selectable between
2.5V and 4.096V using logic input FSSEL. The MAX15500
is specified for a 0 to 4.096V input voltage range, while
the MAX15501 is specified for a 0 to 2.500V input volt-
age range. Connect FSSEL to DVDD to set the input
range to 0 to 4.096V for the MAX15500. Connect FSSEL
to DGND to set the input range to 0 to 2.500V for the
MAX15501.
The MAX15500/MAX15501 are programmed through an
SPI interface with daisy-chain capability. A device ready
logic output (READY) and two device select inputs (CS1
and CS2) facilitate a daisy-chain arrangement for multiple
Table 1. Output Values for FSMODE =
DVDD, Unipolar 5% Overrange
Table 3. Output Values for FSMODE =
DVDD, Bipolar 5% Overrange
OUTPUT VALUES
OUTPUT RANGE
OUTPUT VALUES
OUTPUT RANGE
V
AIN
= 5%FS
V
AIN
= FS
V
AIN
= 0V
V
= FS
AIN
Q20mA
Q10V
-21mA
-10.5V
+21mA
+10.5V
0 to 20mA
(4mA to 20mA)
0mA
21mA
0 to 5V
0V
0V
5.25V
10.5V
0 to 10V
Table 2. Output Values for FSMODE =
DGND, Unipolar 20% Overrange
Table 4. Output Values for FSMODE =
DGND, Bipolar 20% Overrange
OUTPUT VALUES
OUTPUT VALUES
OUTPUT RANGE
OUTPUT RANGE
V
AIN
= 0V
V
= FS
AIN
V
AIN
= 5%FS
V
AIN
= FS
Q20mA
Q10V
-24mA
-12V
+24mA
+12V
0 to 20mA
(4mA to 20mA)
0mA
24mA
0 to 5V
0V
0V
6V
0 to 10V
12V
16 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
resets the ERROR pin but not the error register itself,
allowing the system to determine the source of the error
and take steps to fix the error condition. After the error
condition has been fixed, read the error register for the
second time to allow the device to clear the error reg-
ister. Read the error register for the third time to verify
if the error register has been cleared. If another error
occurs after the first read, ERROR goes low again. More
information on reading and clearing the error register is
described in the SPI Interface section.
Output Monitor
The MON output provides an analog voltage signal
proportional to the output voltage in current mode and
proportional to the output current in voltage mode. Use
this signal to measure the system load presented to the
output. The full-scale signal on MON is 3V with a typical
accuracy of 10%. The signal range is typically 1.5V to 3V
in unipolar mode and 0 to 3V in bipolar mode.
In current mode, the MAX15500/MAX15501 program I
and monitor the voltage at SENSERN.
OUT
When an output short-circuit or output open-load error
occurs and disappears before the error register is read,
the intermittent bit is set in the error register. The intermit-
tent bit does not assert for brownout and overtempera-
ture error conditions.
V
= 1.425V + (V
/20)
MON
SENSERN
R
= ((V
- 1.425V) x 20)/I
MON OUT(PROGRAMMED)
LOAD
In voltage mode, the MAX15500/MAX15501 program
and monitor I
V
OUT
.
OUT
V
= 1.521V + 62.4 x I
LOAD
MON
Error Conditions
Output Short Circuit
R
LOAD
= V
/((V
- 1.521V)/62.4)
OUT(PROGRAMMED)
MON
The output short-circuit error bit asserts when the output
current exceeds 30mA (typ) for longer than 260ms. In
current mode, this error occurs when the sense resistor
is shorted and the sense voltage is not equal to 0V. In
voltage mode, this error occurs when the load is shorted
to the supply or ground. The short-circuit error activates
the intermittent bit in the error register if the error goes
away before the error register is read.
Error Handling
Many industrial control systems require error detection
and handling. The MAX15500/MAX15501 provide exten-
sive error status reporting.
An open-drain interrupt flag output, ERROR, pulls low
when an error condition is detected. An error register
stores the error source. Reading the error register once
V
OUT
OR I
OUT
V
OR I
OUT
FS + 20%
FS + 5%
OUT
FS
FS + 20%
FS + 5%
FSMODE = DGND
FS
FSMODE = DGND
V
AIN
50%FS
FSMODE = DVDD
FSMODE = DVDD
-FS
-FS - 5%
V
AIN
FS
-FS - 20%
5%FS
FS
Figure 1. Unipolar Transfer Function
Figure 2. Bipolar Transfer Function
______________________________________________________________________________________ 17
Industrial Analog Current/
Voltage-Output Conditioners
Output Open Load
Output Protection
The open-circuit error bit activates when V
is within
The MAX15500/MAX15501 supply inputs (AVDD, AVDDO,
AVSS, and AVSSO) and sense inputs (SENSERN,
SENSERP, SENSEVN, and SENSEVP) are protected
against voltages up to Q35V with respect to AGND. See
the Typical Operating Circuit/Functional Diagram for the
recommended supply-voltage connection.
OUT
30mV of AVDDO or AVSSO and there is no short-circuit
current in current mode for longer than 260ms. This error
activates the intermittent bit in the error register if the
error goes away before the error register is read.
Internal Overtemperature
The MAX15500/MAX15501 enter standby mode if the die
temperature exceeds +150NC and the overtemperature
protection is enabled as shown in Table 6. When the die
temperature cools down below +140NC, the error regis-
ter must be read back twice to resume normal operation.
The devices provide a 10NC hysteresis.
SPI Interface
Standard SPI Implementation
The MAX15500/MAX15501 SPI interface supports daisy-
chaining. Multiple MAX15500/MAX15501 devices can
be controlled from a single 4-wire SPI interface. The
MAX15500/MAX15501 feature dual CS_ inputs and
an added digital output, READY, that signals when
the devices finish processing the SPI frame. CS1 and
CS2 are internally OR-ed. Pull both CS1 and CS2 to
logic-low to activate the MAX15500/MAX15501. For a
daisy-chained application, connect the CS1 input of
all of the devices in the chain to the CS driver of the
microcontroller. Connect the CS2 input of the first device
to ground or to the CS driver of the microcontroller.
Connect CS2 of the remaining devices to the READY
output of the preceding device in the chain. The READY
output of the last device in the chain indicates when
all slave devices in the chain are configured. Connect
the READY output of the last device in the chain to the
microcontroller. Use the open-drain ERROR output as a
wired-OR interrupt. See Figures 3 to 6.
Brownout
The brownout-error bit activates when the supply voltage
(V
AVDD
or V ) falls below the brownout threshold.
AVSS
The threshold is programmable between Q10V to Q24V
in 2V steps. See Table 6 for details. The MAX15500/
MAX15501 provide a 2% hysteresis for the brownout
threshold. The accuracy of the threshold is typically
within 10%. During power-up, ERROR can go low and
the brownout register is set. Users need to read out the
error register twice to clear all the error register bits and
reset ERROR to high.
TO OTHER CHIPS/CHAINS
R
PULLUP
FC
CSn
MAX15500
MAX15501
CS1
CS
CS2
CS1
SCLK
SCLK
DIN
DWRITE
DOUT
ERROR
READY
DREAD
INT
MONITOR
OPTIONAL CONNECTION
Figure 3. Single Connection (Compatible with Standard SPI)
18 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
TO OTHER CHIPS/CHAINS
R
PULLUP
FC
CSn
MAX15500
MAX15501
CS1
CS
CS2
CS1
SCLK
SCLK
DIN
DWRITE
DOUT
ERROR
READY
DREAD
INT
MONITOR
OPTIONAL CONNECTION
Figure 4. Alternate Single Connection (Compatible with Standard SPI)
TO OTHER CHIPS/CHAINS
R
PULLUP
FC
CSn
MAX15500
MAX15501
CS1
CS
CS2
CS1
SCLK
SCLK
DIN
DWRITE
DOUT
ERROR
READY
DREAD
INT
MONITOR
MAX15500
MAX15501
CS2
CS1
SCLK
DIN
DOUT
ERROR
READY
MAX15500
MAX15501
CS2
CS1
SCLK
DIN
DOUT
ERROR
READY
OPTIONAL CONNECTION
Figure 5. Daisy-Chain Connection (Compatible with Standard SPI)
______________________________________________________________________________________ 19
Industrial Analog Current/
Voltage-Output Conditioners
TO OTHER CHIPS/CHAINS
R
PULLUP
FC
CSn
MAX15500
MAX15501
CS1
CS
CS2
CS1
SCLK
SCLK
DIN
DWRITE
DOUT
ERROR
READY
DREAD
INT
MAX15500
MAX15501
CS2
CS1
SCLK
DIN
DOUT
ERROR
READY
SPI DEVICE
CS
SCLK
DIN
DOUT
Figure 6. Daisy-Chain Terminating (Compatible with Standard SPI)
Modified SPI Interface Description
low. A new communication cycle is initiated by a sub-
sequent falling edge on CS1 or CS2. When either CS1
or CS2 is high, the MAX15500/MAX15501 SPI interface
deactivates, DOUT returns to a high-impedance mode,
READY (if active) clears, and any partial frames not yet
processed are ignored.
The SCLK, DIN, and DOUT of the MAX15500/MAX15501
assume standard SPI functionality. While the basic func-
tion of the MAX15500/MAX15501 CS_ inputs is similar
to the standard SPI interface protocol, the management
of the CS_ input within the chain is modified. When both
CS_ inputs are low, the MAX15500/MAX15501 assume
control of the DOUT line and continue to control the line
until the data frame is finished and READY goes low
(Figure 9). Once a complete frame is processed and the
READY signal is issued, the devices do not accept any
data from DIN, until either CS1 or CS2 rises and returns
READY asserts once a valid frame is processed allowing
the next device in the chain to begin processing the sub-
sequent frame. A valid frame consists of 16 SCLK cycles
following the falling edge of CS_. Once READY asserts,
it remains asserted until either CS_ rises, completing the
programming of the chain.
20 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
The MAX15500/MAX15501 relinquish control of DOUT
monitor input on the microcontroller. The MAX15500/
MAX15501 portion of the chain continues to display tim-
ing parameters comparable to a single device.
once the devices process the frame(s). DOUT remains
high impedance when the SPI interface continues to hold
CS_ low beyond the required frame(s). Install a pullup/
puldown resistor at the DOUT line to maintain the desired
state when DOUT goes high impedance.
SPI Digital Specifications and Waveforms
Figures 8, 9, and 10 show the operation of the modified
SPI interface. The minimum programming operation
typically used in single device applications is 16 SCLK
periods, the minimum for a valid frame. This cycle can
also represent the operation of the final device in a chain.
Single Device SPI Connection
For applications using a single MAX15500 or MAX15501,
connect both CS1 and CS2 inputs to the device-select
driver of the host microcontroller. Alternatively, connect
one of the CS_ inputs to the device-select driver of the
host microcontroller and the other CS_ to DGND. Both
methods allow standard SPI interface operation. See
Figures 3 and 4.
The extended programming operation is typically used
for devices in daisy-chained applications. In this case,
READY drives the chip-select input of the subsequent
device in the chain. The next device in the chain
begins its active frame on the 16th SCLK falling edge in
response to READY falling (latching DIN[13] on the 17th
SCLK falling edge, if present).
Daisy-Chain SPI Connection
The MAX15500/MAX15501-modified SPI interface allows
a single SPI master to drive multiple devices in a daisy-
chained configuration, saving additional SPI channels for
other devices and saving cost in isolated applications.
Aborted SPI Operations
Driving a CS_ input high before a valid SPI frame is
transmitted to the device can cause an erroneous com-
mand. Avoid driving CS_ high before a valid SPI frame is
transmitted to the device. See Figures 9 and 10 for valid
SPI operation timing.
Figure 5 shows multiple MAX15500/MAX15501 devices
connected in a daisy chain. The chain behaves as a
single device to the microcontroller in terms of timing
with an expanded instruction frame requiring 16 SCLK
cycles per device for complete programming. No timing
parameters are affected by the READY propagation as
all devices connect to the microcontroller chip-select
through the CS1 inputs.
SPI Operation Definitions
Input data bits DIN[13:11] represent the SPI command
address while DIN[9:0] represent the data written to
or read from the command address. The command
address directs subsequent input data to the proper
internal register for setting up the behavior of the device
and selects the correct status data for readback through
DOUT. Command address 0h points to a no-op com-
mand and does not impact the operation of the device.
DOUT is active during this operation and reads back
00h. Command address 1h points to the configuration
register used to program the MAX15500/MAX15501.
Device configuration takes effect following the 14th
SCLK falling edge. DOUT activates and remains low dur-
ing this operation. Command addresses 4h and 5h point
to readback commands of the MAX15500/MAX15501.
Readback commands provide configuration and error
register status through DOUT[9:0] and do not affect the
internal operation of the device. Command addresses
2h, 3h, 6h, and 7h are reserved for future use. Table 5
shows the list of commands.
A chain of MAX15500/MAX15501 devices can be termi-
nated with any standard SPI-compatible single device
without a READY output. The MAX15500/MAX15501 por-
tion of the chain continues to display timing parameters
comparable to a single device. See Figure 6.
When using the MAX15500/MAX15501 with mixed
chains, the connections could require some modification
to accommodate the interfaces of the additional devices
in the chain. Construct the daisy chain as shown in
Figure 7 when using devices with similar READY outputs
but without dual CS_ inputs such as the MAX5134 quad
16-bit DAC. The chain is subject to timing relaxation for
parameters given with respect to CS_ rising edges to
accommodate READY propagation to and through con-
secutive MAX5134 devices.
The chain can begin and terminate with either device
type. Each MAX5134 or MAX15500/MAX15501 device
in the chain could be replaced by a subchain of similar
devices. If the chain is terminated with a standard SPI
device, omit the optional connection from READY to the
Device Configuration Operation
Table 6 shows the function of each bit written to the con-
figuration register 1h. Table 7 shows the data readback
registers.
______________________________________________________________________________________ 21
Industrial Analog Current/
Voltage-Output Conditioners
TO OTHER CHIPS/CHAINS
R
PULLUP
FC
CSn
MAX15500
MAX15501
CS1
CS
CS2
CS1
SCLK
SCLK
DIN
DWRITE
DOUT
ERROR
READY
DREAD
INT
MONITOR
MAX15500
MAX15501
CS2
CS1
SCLK
DIN
DOUT
ERROR
READY
MAX5134
CS
SCLK
DIN
READY
OPTIONAL CONNECTION
Figure 7. Mixed MAX15500/MAX15501 and MAX5134 Daisy-Chain Connections
ERROR REGISTER UPDATED,
ERROR RE-EVALUATED
COMMAND EXECUTED
ACTIVE FRAME
X
Z
DIN13 DIN12 DIN11 DIN10 DIN9 DIN8 DIN7 DIN6 DIN5 DIN4 DIN3 DIN2 DIN1 DIN0
X
X
X
X
DIN
t
DS
t
CP
t
CH
SCLK
t
1
2
3
4
5
6
7
t
8
9
10
11
14
12
13
15
16
t
t
t
CL
DOH
CSS
t
DOZ
t
DOT
CSH
CH
HIGH-Z
DOUT
DOUT9 DOUT8 DOUT7 DOUT6 DOUT5 DOUT4 DOUT3 DOUT2 DOUT1 DOUT0
t
DOE
t
CSH
CS_
t
CSW
Figure 8. Minimum SPI Programming Operation (Typically for Single Device Applications)
22 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
ACTIVE FRAME
X
Z
DIN13 DIN12 DIN11 DIN10 DIN9 DIN8 DIN7 DIN6 DIN5 DIN4 DIN3 DIN2 DIN1 DIN0
X
X
X
X
DIN
t
t
DS
CP
t
CH
SCLK
t
1
2
3
4
5
6
7
t
8
9
10
11
14
12
13
15
16
17
t
t
t
CL
DOH
CSS
t
DOZ
t
DOT
CSH
CH
HIGH-Z
DOUT
DOUT9 DOUT8 DOUT7 DOUT6 DOUT5 DOUT4 DOUT3 DOUT2 DOUT1 DOUT0
t
CSV
t
DOE
CS_
t
CR
t
CSR
READY
Figure 9. Extended SPI Programming Operation (Daisy-Chained Applications)
ERROR REGISTER UPDATED,
ERROR RE-EVALUATED
SCLK
X
1
2
3
4
5
6
7
8
9
10
11
14
12
13
15
16
t
CSS
t
CSH
Z
HIGH-Z
DOUT
DOUT9
t
t
DOE
CSDOZ
CS_
OPERATION ABORTED
Figure 10. Aborted SPI Programming Operation (Invalid, Showing t
and Internal Activity)
CSDOZ
Readback Operations
Write to the command addresses 4h or 5h to read back the
configuration register data or the internal error information
through DOUT[9:0]. For error readback operations, each
bit corresponds to a specific error condition, with multiple
bits indicating multiple error conditions present.
temperature and supply voltage brownout do not trigger
the intermittent bit.
Error Reporting Applications
The ERROR output is typically connected to an inter-
rupt input of the system microcontroller. The MAX15500/
MAX15501 only issue an interrupt when a new error con-
dition is detected. The devices do not issue interrupts
when errors (either individual or multiple) are resolved
or when already reported errors persist. The system
microcontroller resets ERROR when the system micro-
controller reads back the error register. ERROR does not
assert again unless a different error occurs.
Intermittent Errors
An intermittent error is defined as an error that is detected
and is resolved before the error register is read back.
When the error is resolved without intervention, the inter-
mittent bit (bit 9) is set. The output short-circuit and output
open-load errors trigger the intermittent bit. Internal over-
______________________________________________________________________________________ 23
Industrial Analog Current/
Voltage-Output Conditioners
Table 5. SPI Commands
COMMAND
ADDRESS
DIN[13:11]
NAME
DESCRIPTION
000
001
010
011
100
101
110
111
No-op
No operation.
Write configuration
Reserved
Write device configuration register. See Table 6 for details.
Reserved, no operation.
Reserved
Reserved, no operation.
Read error
Read error register status. See Table 7 for details.
Read device configuration register. See Table 6 for details.
Reserved, no operation.
Read configuration
Reserved
Reserved
Reserved, no operation.
Table 6. Configuration Register
LOCATION
FUNCTION
DESCRIPTION
100 Mode[4]: Standby
Sets device operating mode.
000 Mode[0]: Standby
DIN[9:7]
Mode[2:0]
001 Mode[1]: Bipolar current: Q20mA
010 Mode[2]: Unipolar current: 0 to 20mA
011 Mode[3]: Unipolar current: 4mA to 20mA
101 Mode[5]: Bipolar voltage: Q10V
110 Mode[6]: Unipolar voltage: 0 to 10V
111 Mode[7]: Unipolar voltage: 0 to 5V
Sets supply voltage brownout threshold for error reporting.
000: Q10V
001: Q12V
010: Q14V
011: Q16V
100: Q18V
101: Q20V
110: Q22V
111: Q24V
DIN[6:4]
DIN[3]
VBOTH[2:0]
Thermal
shutdown
0 = thermal protection off. 1 = thermal protection on.
Reserved
DIN[10],
DIN[2:0]
—
Note: Modes 2h and 3h are functionally identical.
Table 7. Readback Operations and Formatting
DOUT BITS
DESCRIPTION
COMMAND ADDRESS DIN[13:11] = 101. READBACK DEVICE CONFIGURATION REGISTER
DOUT[9:0]
See configuration register details in Table 6.
COMMAND ADDRESS DIN[13:11] = 100. READBACK ERROR REGISTER
DOUT[9]
DOUT[8]
Output intermittent fault. For details, see the Error Handling section.
Output short circuit. This bit asserts when I > 30mA in voltage and current modes for longer than 260ms.
OUT
Output open load. This bit asserts when V
condition for longer than 260ms.
is within 30mV of AVDDO or AVSSO and there is no short-circuit
OUT
DOUT[7]
DOUT[6]
DOUT[5]
Internal overtemperature. This bit asserts when the die temperature exceeds +150NC.
Supply brownout. This bit asserts when either supply has entered the brownout limits. See Table 6 for details.
Reserved
DOUT[4:0]
24 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
Since the MAX15500/MAX15501 do not use a continuous
3) An error that cannot be resolved.
clock signal, the SPI read cycles are used to cycle the
error detection and reporting logic. Continue to poll the
device until the error readback reports an all clear status
when resolving single or multiple errors. See below for
examples of typical error handling situations and the
effects of the SPI read operations.
a) The MAX15500/MAX15501 detect an error condi-
tion and ERROR asserts.
b) The host controller reads the error register for the
first time and resets ERROR. The data indicates to
the host processor which error is active.
c) The host processor takes action to resolve the
error unsuccessfully.
1) Error resolved by the system.
a) The MAX15500/MAX15501 detect an error condi-
d) The host processor reads the error register for the
second time. The data still shows that the error is
present.
tion and ERROR asserts.
b) The host controller reads the error register for the
first time. This has the effect of resetting ERROR.
The data indicates to the host processor which
error is active.
e) The host processor reads the error for the third
time. The data show the error to be unresolved.
ERROR does not respond to the same error until
the error is resolved and reported. ERROR asserts
if different errors occur.
c) The host processor resolves the error successfully.
d) The host processor reads the error register for the
second time. The data still shows that the error is
present as the error persisted for some time after
step b and before step c. If the error is either an
open load or short circuit, the intermittent bit is set.
An overtemperature or a brownout does not set the
intermittent bit. Reading the register a second time
resets the register.
Applications Information
Setting the Output Gain in Current Mode
In current mode, there is approximately 1.0V across the
current-sensing resistors at full scale. The current sens-
ing resistor sets the gain and is calculated as follows:
R
= V
/I
SENSE
SENSE_FS MAX
e) The host reads the error register for a third time.
The data now shows the error is resolved and
future occurrences of this error will trigger ERROR
assertion.
where V
is the full-scale voltage across the
SENSE_FS
sense resistor.
See Table 8 for values of V
.
SENSE_FS
2) Error resolved before the host processor reads error
register.
Output Gain in Voltage Mode
The output gain in voltage mode is fixed as shown in
Table 9.
a) The MAX15500/MAX15501 detect an error condi-
tion and ERROR asserts, but the error resolves
itself.
Selection of the Compensation
Capacitor (C
)
COMP
b) The host controller reads the error register for the
first time resetting ERROR. The data indicates to
the host processor which error is active. The data
also indicates to the host that the error has been
resolved since the intermittent bit is set.
Use Table 10 to select the compensation capacitor.
Layout Considerations
In the current-mode application, use Kelvin and a short
connection from SENSERN and SENSERP to the R
SENSE
c) The host processor reads the error register for the
second time. The data still shows that the error is
active. If the error is for an output fault, the data
also indicates to the host that the error has been
resolved since the intermittent bit is set. Reading
the register a second time resets the register.
terminals to minimize gain-error drift. Balance and mini-
mize all analog input traces for optimum performance.
______________________________________________________________________________________ 25
Industrial Analog Current/
Voltage-Output Conditioners
Table 8. Recommended Current Setting Components
V
OVERRANGE
(%)
BIPOLAR/
UNIPOLAR
V
R
I
OUT
mA)
(
IDEAL
GAIN
IDEAL TRANSFER
FUNCTION
REFIN
(V)
SENSE_FS
(V)
SENSE
MODE
(I)
I
= 0.2625 x (V
-
OUT
AIN
Unipolar
Bipolar
Unipolar
Bipolar
Unipolar
Bipolar
Unipolar
Bipolar
2
1
2
1
2
1
2
1
1.02144
Q1.024
1.02144
Q1.024
42.2
42.2
48.7
48.7
41.2
41.2
47.5
47.5
24.205 0.2625/42.2
0.05 x V
)/42.2
REFIN
+20
+5
I
V
= 0.5 x (V
- 0.5 x
OUT
AIN
Q24.27
20.97
0.5/42.2
0.2625/48.7
0.5/48.7
)/42.2
REFIN
4.096
I
= 0.2625 x (V
-
OUT
AIN
0.05 x V
)/48.7
REFIN
I
V
= 0.5 x (V
- 0.5 x
OUT
AIN
Q21.03
24.5
)/48.7
REFIN
I
= 0.425 x (V
-
OUT
AIN
1.009375
Q1
0.425/41.2
0.8/41.2
0.05 x V
)/41.2
REFIN
+20
+5
I
V
= 0.8 x (V
- 0.5 x
OUT
AIN
Q24.27
21.25
)/41.2
REFIN
2.500
I
= 0.425 x (V
-
OUT
AIN
1.009375
Q1
0.425/47.5
0.8/47.5
0.05 x V
)/47.5
REFIN
I
V
= 0.8 x (V
- 0.5 x
OUT
AIN
Q21.05
)/47.5
REFIN
Table 9. Full-Scale Output Voltages
V
REFIN
(V)
OVERRANGE
(%)
BIPOLAR/
UNIPOLAR
IDEAL
GAIN
IDEAL
TRANSFER FUNCTION
IDEAL V
(V)
OUT
MODE
7
6
5
7
6
5
7
6
5
7
6
5
1.5625
3.125
6.0
V
= 1.5625 x (V - 0.05 x V
)
6.08
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
AIN
REFIN
Unipolar
Bipolar
Unipolar
Bipolar
Unipolar
Bipolar
Unipolar
Bipolar
+20
+5
V
= 3.125 x (V
- 0.05 x V
)
12.16
Q12.288
5.3504
10.7008
Q10.752
5.96719
12.0234
Q12
AIN
REFIN
V
V
V
V
V
V
V
V
V
V
= 6.0 x (V
- 0.5 x V
)
AIN
REFIN
4.096
2.500
1.375
2.75
= 1.375 x (V
- 0.05 x V
REFIN
)
AIN
= 2.75 x (V
- 0.05 x V
)
AIN
AIN
REFIN
5.25
= 5.25 x (V
- 0.5 x V
)
REFIN
2.5125
5.0625
9.6
= 2.5125 x (V
= 5.0625 x (V
- 0.05 x V
REFIN
- 0.05 x V
REFIN
)
)
AIN
AIN
+20
+5
= 9.6 x (V
- 0.5 x V
)
AIN
REFIN
2.175
4.425
8.4
= 2.175 x (V
= 4.425 x (V
- 0.05 x V
)
)
5.16563
10.5094
Q10.5
AIN
AIN
REFIN
- 0.05 x V
REFIN
= 8.4 x (V
- 0.5 x V
)
AIN
REFIN
26 _____________________________________________________________________________________
Industrial Analog Current/
Voltage-Output Conditioners
Table 10. Recommended Compensation Capacitor for Various Load Conditions
MODE
Voltage
Voltage
Voltage
Voltage
Current
Current
Current
Current
Current
Current
Current
Current
Current
Current
Current
Current
C (F)
L
R (kI)
L (H)
L
C
(F)
L
COMP
0 to 1n
1
0
0
1n to 100n
100n to 1F
1Fto 100F
0 to 1n
1
0
1n
1
0
2.2n
4.7n
0
1
0
20 to 750
20 to 750
20 to 750
20 to 750
20 to 750
20 to 750
20 to 750
0 to 20F
20Fto 1m
1m to 50m
0 to 20F
20Fto 1m
1m to 50m
0 to 20F
20Fto 1m
1m to 50m
0 to 20F
20Fto 1m
1m to 50m
0 to 1n
2.2n
100n
1n
0 to 1n
1n to 100n
1n to 100n
1n to 100n
100n to 1F
100n to 1F
100n to 1F
1Fto 100F
1Fto 100F
1Fto 100F
2.2n
100n
2.2n
2.2n
100n
2.2n
2.2n
100n
20 to 750
20 to 750
20 to 750
20 to 750
20 to 750
C = Load capacitance.
L
R = Load resistance.
L
L = Load inductance.
L
C
COMP
= Compensation capacitance.
Chip Information
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PROCESS: BiCMOS
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
32 TQFN-EP
T3255+4
21-0140
90-0012
______________________________________________________________________________________ 27
Industrial Analog Current/
Voltage-Output Conditioners
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
1
7/09
2/11
Initial release
Corrected description of DOUT pin in Pin Description section
—
13
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time.
28
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
©
相关型号：
©2020 ICPDF网 联系我们和版权申明