View MAX5431_325892.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

19-2222; Rev 1; 1/02
15V Digitally Programmable Precision Voltage-Dividers for PGAs
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 35A 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 MAX packages, and specified over the extended temperature range of (-40C to +85C).
Features
o Four Noninverting PGA Gain Configurations: AV = 1, 2, 4, and 8 o Precision 0.025% Ratio Accuracy o On-Chip Matching Resistor for Op Amp BiasCurrent Compensation (MAX5431) o Single-Supply 12V to 15V, or Dual-Supply 12V to 15V Operation o Low 35A Supply Current o CMOS/TTL Logic Compatible 2-Wire Parallel Interface o Space-Saving 8-Pin SOT23 and 10-Pin MAX Packages o 3V Logic Compatibility
MAX5430/MAX5431
Applications
General-Purpose Programmable Noninverting Amplifier Programmable Instrumentation Amplifier
PART
Ordering Information
TEMP RANGE PINGAIN PACKAGE ACCURACY 8 SOT23 8 SOT23 8 SOT23 10 MAX 10 MAX 10 MAX 0.025% 0.09% 0.5% 0.025% 0.09% 0.5%
MAX5430AEKA -40C to +85C MAX5430BEKA -40C to +85C MAX5430CEKA -40C to +85C MAX5431AEUB -40C to +85C MAX5431BEUB -40C to +85C MAX5431CEUB -40C to +85C
Functional Diagram
VDD MAX5430 MAX5431 D0 DECODER D1 MATCH_H MATCH_L VSS GND L MAX5431 ONLY H
Pin Configurations
TOP VIEW
VDD 1 10 D0
W
MATCH_H 2 GND 3 H4 L5
MAX5431
9 D1 8W 7 VSS 6 MATCH_L
MAX Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
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.
15V Digitally Programmable Precision Voltage-Dividers for PGAs MAX5430/MAX5431
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 = +70C) 8-Pin SOT23 (derate 8.9mW/C above +70C)............714mW 10-Pin MAX (derate 10.3mW/C above +70C) .........825mW Operating Temperature Range ...........................-40C to +85C Storage Temperature Range .............................-60C to +150C Junction Temperature ......................................................+150C Lead Temperature (soldering, 10s) .................................+300C
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 = +25C, unless otherwise noted.) (Note 1)
PARAMETER DC PERFORMANCE MAX543_A Divider Ratio Accuracy (Note 2) Resistance between H and L (Figure 1) Capacitance at Analog Pins Matching Resistor W, H, L, MATCH_H, MATCH _L Voltage Range DIGITAL INPUTS Input High Voltage Input Low Voltage Input Leakage Current Input Capacitance POWER REQUIREMENTS Negative Supply Current Positive Supply Current Positive Power-Supply Voltage Negative Power-Supply Voltage DYNAMIC PERFORMANCE Switching Time tD2W, tH2W 0.3 s ISS IDD VDD VSS 10.8 -15.75 1 35 25 60 15.75 0 A A V V CIN VIH VIL D0, D1 = 5V or GND 5 2.4 0.8 1 V V A pF VANALOG RHL CANALOG MAX5431 only Ratio = 1 Ratio = 2, 4, 8 VSS VH = +5V, VL = -5V MAX543_B MAX543_C 57 2 0.5 14 VDD 0.025 0.09 0.5 k pF k V % SYMBOL CONDITIONS MIN TYP MAX UNITS
Note 1: All devices are 100% production tested at TA = +25C. 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
Typical Operating Characteristics
(VDD = +15V, VSS = -15V or VSS = GND, VH = 5V, VL =-5V, TA = 25C, unless otherwise noted.) (Note 3)
MAX5430/MAX5431
MAX543_A DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 1)
MAX5430 toc01
MAX543_A DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 2)
MAX5430 toc02
MAX543_A DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 4)
0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008
MAX5430 toc03
0.0020 0.0015 DIVIDER RATIO ACCURACY (%) 0.0010 0.0005 0 -0.0005 -0.0010 -0.0015 -0.0020 -40 -25 -10 5 20 35 50 65 80 TEMPERATURE (C)
0.010 0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 -40 -25 -10 5 20 35 50 65 80 TEMPERATURE (C)
0.010
-0.010 -40 -25 -10
5
20
35
50
65
80
TEMPERATURE (C)
MAX543_A DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 8)
MAX5430 toc04
MAX543_B DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 1)
MAX5430 toc05
MAX543_B DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 2)
0.015 DIVIDER RATIO ACCURACY (%) 0.010 0.005 0 -0.005 -0.010 -0.015 -0.020 -40 -25 -10
MAX5430 toc06
0.010 0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 -40 -25 -10 5 20 35 50 65 80
0.0020 0.0015 DIVIDER RATIO ACCURACY (%) 0.0010 0.0005 0 -0.0005 -0.0010 -0.0015 -0.0020 -40
0.020
-25 -10
5
20
35
50
65
80
5
20
35
50
65
80
TEMPERATURE (C)
TEMPERATURE (C)
TEMPERATURE (C)
MAX543_B DIVIDER RATIO ACCURACY vs.TEMPERATURE (RATIO = 4)
MAX5430 toc07
MAX543_B DIVIDER RATIO ACCURACY vs. TEMPERATURE (RATIO = 8)
MAX5430 toc08
MAX543_A DIVIDER RATIO ACCURACY vs. POSITIVE SUPPLY (VSS = -15V)
0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 RATIO 4 RATIO 8 RATIO 1 RATIO 2
MAX5430 toc09
0.010 0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 -40 -25 -10 5 20 35 50 TEMPERATURE (C) 65 80
0.010 0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 -40 -25 -10 5 20 35 50 65 80
0.010
11
12
13 POSITIVE SUPPLY (V)
14
15
TEMPERATURE (C)
_______________________________________________________________________________________
3
15V Digitally Programmable Precision Voltage-Dividers for PGAs MAX5430/MAX5431
Typical Operating Characteristics (continued)
(VDD = +15V, VSS = -15V or VSS = GND, VH = 5V, VL =-5V, TA = 25C, unless otherwise noted.) (Note 3)
MAX543_B DIVIDER RATIO ACCURACY vs. POSITIVE SUPPLY (VSS = -15V)
MAX5430 toc10
MAX543_A DIVIDER RATIO ACCURACY vs. POSITIVE SUPPLY (VSS = 0V)
MAX5430 toc11
MAX543_B DIVIDER RATIO ACCURACY vs. POSITIVE SUPPLY (VSS = 0V)
0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 RATIO 1 RATIO 8 RATIO 2 RATIO 4 VL = 0
MAX5430 toc12
0.010 0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 11 12 13 POSITIVE SUPPLY (V) 14 RATIO 8 RATIO 1 RATIO 2 RATIO 4
0.010 0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 RATIO 8 RATIO 1 RATIO 4 RATIO 2
0.010
VL = 0
15
11
12
13 POSITIVE SUPPLY (V)
14
15
11
12
13 POSITIVE SUPPLY (V)
14
15
MAX543_A DIVIDER RATIO ACCURACY vs. NEGATIVE SUPPLY
MAX5430 toc13
MAX543_B DIVIDER RATIO ACCURACY vs. NEGATIVE SUPPLY
0.008 DIVIDER RATIO ACCURACY (%) 0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 0 -15 -12 -9 -6 -3 0 RATIO 1 RATIO 8 RATIO 2 RATIO 4
MAX5430 toc14
SUPPLY CURRENT vs. TEMPERATURE
D0, D1 = 5V 25 SUPPLY CURRENT (A) 20 15 10 5 D0, D1 = 0V
MAX5430 toc15
0.010 0.008
VL = 0 RATIO 2 RATIO 1
0.010
30
DIVIDER RATIO ACCURACY (%)
0.006 0.004 0.002 0 -0.002 -0.004 -0.006 -0.008 -0.010 -15
RATIO 4
RATIO 8
-12
-9
-6
-3
0
-40 -25 -10
5
20
35
50
65
80
NEGATIVE SUPPLY (V)
NEGATIVE SUPPLY (V)
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 Description
PIN NAME MAX5431 1 2 3 4 5 6 7 8 9 10 MAX5430 8 -- 7 6 5 -- 4 3 2 1 VDD MATCH_H GND H L MATCH_L VSS W D1 D0 Positive Power Supply Matching Resistor High Terminal Ground High Terminal of Resistive-Divider Low Terminal of Resistive-Divider Matching Resistor Low Terminal Negative Power Supply Wiper Terminal of Resistive-Divider Second Bit Digital Input (MSB) (Table 1) First Bit Digital Input (LSB) (Table 1) FUNCTION
MAX5430/MAX5431
H
(MAX5430A/MAX5431A), 0.09% (MAX5430B/MAX5431B), or 0.5% (MAX5430C/MAX5431C). The end-to-end resistance from H to L is 57k. The impedance seen at W is designed to be the same 14k 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 500.
RATIO = 1 4R
RATIO = 2 2R W
Matching Resistor (MAX5431)
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 = 4 R
RATIO = 8 R
L
Table 1. Logic-Control Truth Table
DIGITAL INPUTS D1 0 0 1 1 D0 0 1 0 1 GAIN 1 2 4 8
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%
_______________________________________________________________________________________
5
15V Digitally Programmable Precision Voltage-Dividers for PGAs MAX5430/MAX5431
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.
15V VIN VOUT 15V VDD W
Applications Information
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).
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 0.1F ceramic capacitors to GND. For single supply, connect VSS to GND and bypass VDD with a 0.1F ceramic capacitor to GND.
Figure 3. Programmable-Gain Amplifier Using the MAX5430
Pin Configurations (continued)
TOP VIEW
D0 1 D1 2 W3 VSS 4 8 VDD
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
7 6 5
GND H L
SOT23
15V VDD MATCH_H VIN MAX5431 MATCH_L VOUT W 15V
Chip Information
TRANSISTOR COUNT: 121 PROCESS: CMOS
H VSS L GND
Figure 2. MAX5431 Typical Application Circuit
6
_______________________________________________________________________________________
15V Digitally Programmable Precision Voltage-Dividers for PGAs
Package Information
SOT23, 8L.EPS
MAX5430/MAX5431
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 (c) 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
10LUMAX.EPS

▲Up To Search▲

Price & Availability of MAX5431

	To Download MAX5431 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .