MAXIM MAX5430CEKA

19-2222; Rev 1; 1/02
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
Features
♦ Four Noninverting PGA Gain Configurations:
AV = 1, 2, 4, and 8
♦ Precision 0.025% Ratio Accuracy
♦ On-Chip Matching Resistor for Op Amp BiasCurrent 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
Applications
General-Purpose Programmable Noninverting
Amplifier
Programmable Instrumentation Amplifier
Ordering Information
TEMP
RANGE
PART
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
Functional Diagram
VDD
PINGAIN
PACKAGE ACCURACY
H
TOP VIEW
MAX5430
MAX5431
10 D0
VDD 1
W
D0
MATCH_H 2
MAX5431
GND 3
DECODER
9 D1
8 W
D1
H 4
7 VSS
MATCH_H
L 5
6 MATCH_L
MATCH_L
µMAX
VSS GND L
MAX5431 ONLY
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
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.
1
MAX5430/MAX5431
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 resistor-dividers. Each device has digitally controlled contacts 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 specified over the extended temperature range of (-40°C to
+85°C).
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
ABSOLUTE MAXIMUM RATINGS
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
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.
ELECTRICAL CHARACTERISTICS
(VDD = +15V, VSS = -15V, GND = 0, TA = TMIN to TMAX. Typical values are at TA = +25°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC PERFORMANCE
Divider Ratio Accuracy
(Note 2)
VH = +5V, VL = -5V
Resistance between H and L
(Figure 1)
RHL
Capacitance at Analog Pins
CANALOG
Matching Resistor
W, H, L, MATCH_H, MATCH _L
Voltage Range
MAX5431 only
MAX543_A
0.025
MAX543_B
0.09
MAX543_C
0.5
Ratio = 1
Ratio = 2, 4, 8
VANALOG
VSS
Input High Voltage
VIH
2.4
Input Low Voltage
VIL
%
57
kΩ
2
pF
0.5
14
kΩ
VDD
V
DIGITAL INPUTS
Input Leakage Current
Input Capacitance
V
D0, D1 = 5V or GND
CIN
0.8
V
±1
µA
5
pF
POWER REQUIREMENTS
Negative Supply Current
ISS
1
25
µA
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
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.
2
_______________________________________________________________________________________
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 2)
0.0005
0
-0.0005
-0.0010
0.004
0.002
0
-0.002
-0.004
-0.006
-0.0015
-0.008
-0.0020
-0.010
20
35
50
65
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 8)
20
35
50
65
0.004
0.002
0
-0.002
-0.004
-0.006
0.0015
65
0.0005
0
-0.0005
-0.0010
-25 -10
5
20
35
50
65
0.006
0.004
0.002
0
-0.002
-0.004
-0.006
-0.008
5 20 35 50
TEMPERATURE (°C)
MAX5430 toc03
0
-0.005
-0.010
65
80
0.008
0.006
0.004
0.002
0
-0.002
-0.004
-0.006
-0.010
-40 -25 -10
5
20
35
50
65
80
TEMPERATURE (°C)
-0.008
-25 -10
80
0.005
-0.020
-40 -25 -10
80
0.010
DIVIDER RATIO ACCURACY (%)
0.008
65
0.010
MAX543_A DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = -15V)
MAX543_B DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 8)
MAX5430 toc07
0.010
50
0.015
TEMPERATURE (°C)
MAX543_B DIVIDER RATIO ACCURACY
vs.TEMPERATURE (RATIO = 4)
35
-0.015
-0.0020
-40
80
20
0.020
0.010
0.008
DIVIDER RATIO ACCURACY (%)
50
5
MAX543_B DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 2)
0.0010
TEMPERATURE (°C)
-0.010
-40
-0.006
TEMPERATURE (°C)
-0.0015
35
-0.004
-0.010
-40 -25 -10
80
MAX5430 toc05
0.006
-0.008
DIVIDER RATIO ACCURACY (%)
5
0.0020
DIVIDER RATIO ACCURACY (%)
DIVIDER RATIO ACCURACY (%)
0.008
20
0
-0.002
MAX543_B DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 1)
MAX5430 toc04
0.010
5
0.002
TEMPERATURE (°C)
TEMPERATURE (°C)
-0.010
-40 -25 -10
0.004
-0.008
-40 -25 -10
80
0.006
MAX5430 toc06
5
0.008
DIVIDER RATIO ACCURACY (%)
-40 -25 -10
MAX5430 toc02
0.006
0.010
MAX5430 toc09
0.0010
0.008
MAX5430 toc08
DIVIDER RATIO ACCURACY (%)
0.0015
0.010
DIVIDER RATIO ACCURACY (%)
MAX5430 toc01
0.0020
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 4)
DIVIDER RATIO ACCURACY (%)
MAX543_A DIVIDER RATIO ACCURACY
vs. TEMPERATURE (RATIO = 1)
RATIO 2
0.006
0.004
0.002
RATIO 1
0
-0.002
-0.004
RATIO 4
RATIO 8
-0.006
-0.008
-0.010
5
20
35
TEMPERATURE (°C)
50
65
80
11
12
13
14
15
POSITIVE SUPPLY (V)
_______________________________________________________________________________________
3
MAX5430/MAX5431
Typical Operating Characteristics
(VDD = +15V, VSS = -15V or VSS = GND, VH = 5V, VL =-5V, TA = 25°C, unless otherwise noted.) (Note 3)
Typical Operating Characteristics (continued)
(VDD = +15V, VSS = -15V or VSS = GND, VH = 5V, VL =-5V, TA = 25°C, unless otherwise noted.) (Note 3)
0.004
0.002
0
RATIO 8
-0.002
RATIO 1
-0.004
-0.006
-0.008
RATIO 2
0.006
0.004
RATIO 1
0.002
RATIO 4
0
-0.002
-0.004
RATIO 8
-0.006
12
13
14
15
RATIO 2
0.006
RATIO 4
0.004
0.002
0
-0.002
RATIO 8
RATIO 1
-0.004
-0.006
-0.010
-0.010
11
VL = 0
0.008
-0.008
-0.008
-0.010
0.010
11
12
13
14
11
15
12
13
14
POSITIVE SUPPLY (V)
POSITIVE SUPPLY (V)
MAX543_A DIVIDER RATIO ACCURACY
vs. NEGATIVE SUPPLY
MAX543_B DIVIDER RATIO ACCURACY
vs. NEGATIVE SUPPLY
SUPPLY CURRENT
vs. TEMPERATURE
0.006
RATIO 2
0.004
0.002
RATIO 1
RATIO 4
0
-0.002
-0.004
RATIO 8
-0.006
-0.008
0.010
0.008
0.006
RATIO 4
0.004
RATIO 2
0.002
0
-0.002
RATIO 8
RATIO 1
-0.004
-0.006
15
30
D0, D1 = 5V
25
SUPPLY CURRENT (µA)
VL = 0
0.008
DIVIDER RATIO ACCURACY (%)
MAX5430 toc13
POSITIVE SUPPLY (V)
0.010
MAX5430 toc12
VL = 0
0.008
DIVIDER RATIO ACCURACY (%)
RATIO 4
MAX5430 toc11
RATIO 2
0.006
0.010
MAX5430 toc14
DIVIDER RATIO ACCURACY (%)
0.008
DIVIDER RATIO ACCURACY (%)
MAX5430 toc10
0.010
MAX543_B DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = 0V)
MAX543_A DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = 0V)
MAX5430 toc15
MAX543_B DIVIDER RATIO ACCURACY
vs. POSITIVE SUPPLY (VSS = -15V)
DIVIDER RATIO ACCURACY (%)
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
20
15
10
D0, D1 = 0V
5
-0.008
-0.010
-0.010
-15
-12
-9
-6
NEGATIVE SUPPLY (V)
-3
0
0
-15
-12
-9
-6
NEGATIVE SUPPLY (V)
-3
0
-40 -25 -10
5
20
35
50
65
80
TEMPERATURE (°C)
Note 3: For MAX543_C accuracy Typical Operating Characteristics, refer to MAX543_B accuracy Typical Operating Characteristics.
4
_______________________________________________________________________________________
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
PIN
NAME
MAX5431
FUNCTION
MAX5430
1
8
VDD
2
—
MATCH_H
Positive Power Supply
3
7
GND
4
6
H
High Terminal of Resistive-Divider
5
5
L
Low Terminal of Resistive-Divider
6
—
MATCH_L
7
4
VSS
8
3
W
Wiper Terminal of Resistive-Divider
Matching Resistor High Terminal
Ground
Matching Resistor Low Terminal
Negative Power Supply
9
2
D1
Second Bit Digital Input (MSB) (Table 1)
10
1
D0
First Bit Digital Input (LSB) (Table 1)
(MAX5430A/MAX5431A), 0.09% (MAX5430B/MAX5431B),
or 0.5% (MAX5430C/MAX5431C).
H
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 internally connected to W with a typical resistance of 500Ω.
RATIO = 1
4R
RATIO = 2
2R
Matching Resistor (MAX5431)
W
RATIO = 4
R
The MAX5431 includes a matching resistor to compensate 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 impedance of the switch between H and W.
RATIO = 8
R
Table 1. Logic-Control Truth Table
L
DIGITAL INPUTS
Figure 1. Simplified Functional Diagram
Detailed Description
The MAX5430/MAX5431 are digitally programmable precision resistor arrays. These devices have fixed resistordividers 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%
GAIN
D1
D0
0
0
1
0
1
2
1
0
4
1
1
8
_______________________________________________________________________________________
5
MAX5430/MAX5431
Pin Description
MAX5430/MAX5431
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
Digital Interface Operation
The MAX5430/MAX5431 feature a simple two-bit parallel 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 compatible.
Applications Information
15V
VIN
VOUT
15V
VDD
Programmable-Gain Amplifier
The MAX5430/MAX5431 are ideally suited for high-precision 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).
W
H
MAX5430
VSS
L
GND
Power Supplies and Bypassing
The MAX5430/MAX5431 operate from dual ±15V supplies 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.
Figure 3. Programmable-Gain Amplifier Using the MAX5430
Pin Configurations (continued)
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.
TOP VIEW
8 VDD
D0 1
D1 2
MAX5430
W 3
VSS 4
7
GND
6
H
5
L
SOT23
Chip Information
15V
TRANSISTOR COUNT: 121
PROCESS: CMOS
15V
VDD
MATCH_H
VIN
MATCH_L
VOUT
MAX5431
W
H
VSS
L
GND
Figure 2. MAX5431 Typical Application Circuit
6
_______________________________________________________________________________________
±15V Digitally Programmable
Precision Voltage-Dividers for PGAs
SOT23, 8L.EPS
10LUMAX.EPS
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 7
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX5430/MAX5431
Package Information