General Description
The MAX5430/MAX5431 are digitally programmable
high-precision resistor arrays for PGAs. The MAX5430/
MAX5431 operate from a single 15V supply or dual
±15V supplies, and consume only 35µA supply current.
These devices are intended for programmable-gain
amplifier (PGA) applications and consist of fixed resis-
tor-dividers. Each device has digitally controlled con-
tacts with four precision noninverting gains of 1, 2, 4,
and 8 with ratio accuracy of 0.025% (MAX5430A/
MAX5431A), 0.09% (MAX5430B/MAX5431B), or 0.5%
(MAX5430C/MAX5431C). The MAX5431 includes an
on-chip matching resistor for op amp input bias-current
compensation.
The MAX5430/MAX5431 are available in space-saving
8-pin SOT23 and 10-pin µMAX packages, and speci-
fied over the extended temperature range of (-40°C to
+85°C).
Applications
General-Purpose Programmable Noninverting
Amplifier
Programmable Instrumentation Amplifier
Features
♦Four Noninverting PGA Gain Configurations:
AV= 1, 2, 4, and 8
♦Precision 0.025% Ratio Accuracy
♦On-Chip Matching Resistor for Op Amp Bias-
Current Compensation (MAX5431)
♦Single-Supply 12V to 15V, or Dual-Supply ±12V to
±15V Operation
♦Low 35µA Supply Current
♦CMOS/TTL Logic Compatible 2-Wire Parallel
Interface
♦Space-Saving 8-Pin SOT23 and 10-Pin µMAX
Packages
♦3V Logic Compatibility
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
________________________________________________________________ Maxim Integrated Products 1
1
2
3
4
5
10
9
8
7
6
GND
MATCH_L
MATCH_H
VDD
MAX5431
µMAX
TOP VIEW
H
W
D0
D1
VSS
L
Pin Configurations
Ordering Information
DECODER
MATCH_H
MATCH_L
MAX5431 ONLY
H
VDD
W
L
GND
VSS
MAX5430
MAX5431
D0
D1
Functional Diagram
19-2222; Rev 1; 1/02
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
PART TEMP
RANGE
PIN-
PACKAGE
GAIN
ACCURACY
MAX5430AEKA -40°C to +85°C 8 SOT23 0.025%
MAX5430BEKA -40°C to +85°C 8 SOT23 0.09%
MAX5430CEKA -40°C to +85°C 8 SOT23 0.5%
MAX5431AEUB -40°C to +85°C 10 µMAX 0.025%
MAX5431BEUB -40°C to +85°C 10 µMAX 0.09%
MAX5431CEUB -40°C to +85°C 10 µMAX 0.5%
Pin Configurations continued at end of data sheet.
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VDD = +15V, VSS = -15V, GND = 0, TA= TMIN to TMAX. Typical values are at TA= +25°C, unless otherwise noted.) (Note 1)
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.
Note 1: All devices are 100% production tested at TA= +25°C. SOT23 packages are guaranteed by design from TA= TMIN to TMAX.
Note 2: Gain accuracy is measured without load at pin W.
VDD to GND............................................................-0.3V to +17V
VSS to GND.............................................................-17V to +0.3V
D0, D1 to GND .........................................................-0.3V to +6V
H, L, W, MATCH_ to GND ................(VSS - 0.3V) to (VDD + 0.3V)
Current Into Any Signal Pin...............................................±50mA
Continuous Power Dissipation (TA= +70°C)
8-Pin SOT23 (derate 8.9mW/°C above +70°C)............714mW
10-Pin µMAX (derate 10.3mW/°C above +70°C) .........825mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-60°C to +150°C
Junction Temperature......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DC PERFORMANCE
MAX543_A 0.025
MAX543_B 0.09
Divider Ratio Accuracy
(Note 2) VH = +5V, VL = -5V
MAX543_C 0.5
%
Resistance between H and L
(Figure 1) RHL 57 kΩ
Capacitance at Analog Pins CANALOG 2pF
Ratio = 1 0.5
Matching Resistor MAX5431 only Ratio = 2, 4, 8 14 kΩ
W, H, L, MATCH_H, MATCH _L
Voltage Range VANALOG VSS VDD V
DIGITAL INPUTS
Input High Voltage VIH 2.4 V
Input Low Voltage VIL 0.8 V
Input Leakage Current D0, D1 = 5V or GND ±1 µA
Input Capacitance CIN 5pF
POWER REQUIREMENTS
Negative Supply Current ISS 125µA
Positive Supply Current IDD 35 60 µA
Positive Power-Supply Voltage VDD 10.8 15.75 V
Negative Power-Supply Voltage VSS -15.75 0 V
DYNAMIC PERFORMANCE
Switching Time tD2W
,
tH2W 0.3 µs
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
_______________________________________________________________________________________ 3
-0.0020
-0.0015
-0.0005
-0.0010
0
0.0005
0.0015
0.0020
0.0010
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 1)
MAX5430 toc01
DIVIDER RATIO ACCURACY (%)
-0.010
-0.006
-0.008
-0.002
-0.004
0.002
0
0.004
0.008
0.010
0.006
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 2)
MAX5430 toc02
DIVIDER RATIO ACCURACY (%)
-0.010
-0.006
-0.008
-0.002
-0.004
0.002
0
0.004
0.008
0.006
0.010
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 4)
MAX5430 toc03
DIVIDER RATIO ACCURACY (%)
-0.010
-0.006
-0.008
-0.002
-0.004
0.002
0
0.004
0.008
0.006
0.010
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 8)
MAX5430 toc04
DIVIDER RATIO ACCURACY (%)
-0.0020
-0.0015
-0.0005
-0.0010
0.0005
0
0.0010
0.0015
0.0020
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_B DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 1)
MAX5430 toc05
DIVIDER RATIO ACCURACY (%)
-0.020
-0.015
-0.005
-0.010
0
0.005
0.015
0.010
0.020
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_B DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 2)
MAX5430 toc06
DIVIDER RATIO ACCURACY (%)
-0.010
-0.006
-0.008
-0.004
0
-0.002
0.010
0.008
0.006
0.004
0.002
-40 -10 5 20-25 35 50 65 80
MAX543_B DIVIDER RATIO ACCURACY
vs.TEMPERATURE (RATIO = 4)
MAX5430 toc07
DIVIDER RATIO ACCURACY (%)
TEMPERATURE (°C)
-0.010
-0.006
-0.008
-0.002
-0.004
0.002
0
0.004
0.008
0.006
0.010
-40 -10 5 20
TEMPERATURE (°C)
-25 35 50 65 80
MAX543_B DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 8)
MAX5430 toc08
DIVIDER RATIO ACCURACY (%)
-0.010
-0.006
-0.008
-0.004
0
0.004
0.006
0.008
0.010
11 12 13 14 15
MAX543_A DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = -15V)
MAX5430 toc09
POSITIVE SUPPLY (V)
DIVIDER RATIO ACCURACY (%)
RATIO 1
-0.002
0.002
RATIO 2
RATIO 8
RATIO 4
Typical Operating Characteristics
(VDD = +15V, VSS = -15V or VSS = GND, VH= 5V, VL=-5V, TA= 25°C, unless otherwise noted.) (Note 3)
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
4 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(VDD = +15V, VSS = -15V or VSS = GND, VH= 5V, VL=-5V, TA= 25°C, unless otherwise noted.) (Note 3)
-0.010
-0.004
-0.006
-0.008
-0.002
0
0.002
0.004
0.006
0.008
0.010
11 12 13 14 15
MAX543_B DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = -15V)
MAX5430 toc10
POSITIVE SUPPLY (V)
DIVIDER RATIO ACCURACY (%)
RATIO 2 RATIO 4
RATIO 1
RATIO 8
11 12 13 14 15
MAX543_A DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = 0V)
MAX5430 toc11
POSITIVE SUPPLY (V)
DIVIDER RATIO ACCURACY (%)
RATIO 2
RATIO 4
RATIO 1
RATIO 8
-0.010
-0.004
-0.006
-0.008
-0.002
0
0.002
0.004
0.006
0.008
0.010 VL = 0
-0.010
-0.004
-0.006
-0.008
-0.002
0
0.002
0.004
0.006
0.008
0.010
11 12 13 14 15
MAX543_B DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = 0V)
MAX5430 toc12
POSITIVE SUPPLY (V)
DIVIDER RATIO ACCURACY (%)
RATIO 2
RATIO 4
RATIO 1 RATIO 8
VL = 0
-15 -12 -6-9 -3 0
MAX543_A DIVIDER RATIO ACCURACY
vs. NEGATIVE SUPPLY
MAX5430 toc13
NEGATIVE SUPPLY (V)
DIVIDER RATIO ACCURACY (%)
-0.010
-0.004
-0.006
-0.008
-0.002
0
0.002
0.004
0.006
0.008
0.010
RATIO 2
RATIO 1
RATIO 8
RATIO 4
VL = 0
0
10
5
20
15
25
30
-40 -10 5 20-25 35 50 65 80
SUPPLY CURRENT
vs. TEMPERATURE
MAX5430 toc15
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
D0, D1 = 0V
D0, D1 = 5V
Note 3: For MAX543_C accuracy Typical Operating Characteristics, refer to MAX543_B accuracy Typical Operating Characteristics.
-15 -12 -6-9 -3 0
MAX543_B DIVIDER RATIO ACCURACY
vs. NEGATIVE SUPPLY
MAX5430 toc14
NEGATIVE SUPPLY (V)
DIVIDER RATIO ACCURACY (%)
-0.010
-0.004
-0.006
-0.008
-0.002
0
0.002
0.004
0.006
0.008
0.010
RATIO 2
RATIO 1 RATIO 8
RATIO 4
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
_______________________________________________________________________________________ 5
Pin Description
PIN
MAX5431 MAX5430
NAME FUNCTION
18V
DD Positive Power Supply
2—MATCH_H Matching Resistor High Terminal
3 7 GND Ground
4 6 H High Terminal of Resistive-Divider
5 5 L Low Terminal of Resistive-Divider
6—MATCH_L Matching Resistor Low Terminal
74V
SS Negative Power Supply
8 3 W Wiper Terminal of Resistive-Divider
9 2 D1 Second Bit Digital Input (MSB) (Table 1)
10 1 D0 First Bit Digital Input (LSB) (Table 1)
Detailed Description
The MAX5430/MAX5431 are digitally programmable pre-
cision resistor arrays. These devices have fixed resistor-
dividers with digitally controlled contacts, providing four
precision noninverting gains of 1, 2, 4, and 8 for PGA
applications (see Functional Diagram and Figure 1). The
MAX5430/MAX5431 achieve ratio accuracies of 0.025%
(MAX5430A/MAX5431A), 0.09% (MAX5430B/MAX5431B),
or 0.5% (MAX5430C/MAX5431C).
The end-to-end resistance from H to L is 57kΩ. The
impedance seen at W is designed to be the same 14kΩ
for gain settings 2, 4, and 8, ensuring excellent op amp
input-resistance balance, regardless of gain setting
(MAX5431 only). In a gain of 1 configuration, H is inte-
rnally connected to W with a typical resistance of 500Ω.
Matching Resistor (MAX5431)
The MAX5431 includes a matching resistor to compen-
sate the offset voltage due to the input bias current of
the op amp. The resistance from MATCH_H to
MATCH_L is a fixed matching resistor, equal to the
resistance seen at W for gains of 2, 4, and 8. In the
gain of 1, an internal switch short circuits MATCH_H
and MATCH_L. This internal switch matches the imped-
ance of the switch between H and W.
Figure 1. Simplified Functional Diagram
4R
2R
RATIO = 2
RATIO = 1
R
L
W
H
RATIO = 4
RATIO = 8
R
DIGITAL INPUTS
D1 D0 GAIN
00 1
01 2
10 4
11 8
Table 1. Logic-Control Truth Table
Digital Interface Operation
The MAX5430/MAX5431 feature a simple two-bit paral-
lel programming interface. D1 and D0 program the gain
setting according to the Logic-Control Truth Table (see
Table 1). The digital interface is CMOS/TTL logic com-
patible.
Applications Information
Programmable-Gain Amplifier
The MAX5430/MAX5431 are ideally suited for high-pre-
cision PGA applications. The typical application circuit
of Figure 2 uses the MAX5431 with matching resistor to
compensate for voltage offset due to op amp input bias
currents. Use the MAX5430 with an ultra-low input bias
current op amp (see Figure 3).
Power Supplies and Bypassing
The MAX5430/MAX5431 operate from dual ±15V sup-
plies or a single 15V supply. For dual supplies, bypass
VDD and VSS with 0.1µF ceramic capacitors to GND.
For single supply, connect VSS to GND and bypass
VDD with a 0.1µF ceramic capacitor to GND.
Switching Time and Layout Concerns
The switching time of the MAX5430/MAX5431 depends
on the capacitive loading at W. For best performance,
reduce parasitic board capacitance by minimizing the
circuit board trace from W to the op amp inverting input,
and choose an op amp with low input capacitance.
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
6 _______________________________________________________________________________________
15V
MATCH_L
W
H
15V
MATCH_H
VSS
VDD
GNDL
MAX5431
VIN
VOUT
15V
W
H
15V
VSS
VDD
GNDL
MAX5430
VIN
VOUT
Figure 2. MAX5431 Typical Application Circuit
Figure 3. Programmable-Gain Amplifier Using the MAX5430
Pin Configurations (continued)
Chip Information
TRANSISTOR COUNT: 121
PROCESS: CMOS
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
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.
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Package Information
SOT23, 8L.EPS
10LUMAX.EPS