19-127; Rev. 1; 11/98 General Description The MAX478 and MAX479 are dual and quad micropower, precision op amps available in 8-pin and 14-pin DIP and small-outline packages, respectively. Both devices feature an extremely low, 17µA max supply current per op amp, 7µ max offset voltage, 2.2µ/ C max offset voltage drift (.5µ/ C typ), and 25pA max input offset current. The MAX478 and MAX479 operate from a single supply. The input voltage range includes ground, and the output swings to within a few millivolts of ground, which eliminates pull-down resistors and saves power. Both devices are optimized for single 3 and 5 supply operation, with guaranteed specifications at each supply voltage. Specifications for ±15 operation are also provided. Applications Battery- or Solar-Powered Systems: Portable Instrumentation Remote Sensor Amplifier Satellite Circuitry Micropower Sample-and-Hold Thermocouple Amplifier Micropower Filters Single Lithium Cell Powered Systems Features 17µA Max Supply Current (MAX478A/MAX479A) 7µ Max Offset oltage (MAX478A) Single-Supply Operation: Input oltage Range Includes Ground Output Swings to Ground While Sinking Current No Pull-Down Resistors Required Dual Op Amp in 8-Pin DIP/SO Package (MAX478) Quad Op Amp in 14-Pin DIP/SO Package (MAX479) 25pA Max Input Offset Current (MAX478A/MAX479A).5µ/ C Offset-oltage Drift Output Sources and Sinks 5mA Load Current Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX478ACPA C to +7 C 8 Plastic DIP MAX478CPA C to +7 C 8 Plastic DIP MAX478CSA C to +7 C 8 SO MAX478C/D C to +7 C Dice* MAX478EPA -4 C to +85 C 8 Plastic DIP MAX478ESA -4 C to +85 C 8 SO MAX479ACPD C to +7 C 14 Plastic DIP MAX479CPD C to +7 C 14 Plastic DIP MAX479CSD C to +7 C 14 SO MAX479EPD -4 C to +85 C 14 Plastic DIP MAX479ESD -4 C to +85 C 14 SO * Dice are specified at, DC parameters only. Pin Configurations Typical Operating Circuit TOP IEW OUTA 1 8 + R3 R1 R2 R2 R1 OUTB INB- INB+ INA- INA+ - 2 3 4 A MAX478 B 7 6 5 +5 DIP/SO 2 1 1/2MAX478 MICROPOWER, HIGH INPUT IMPEDANCE DIFFERENTIAL AMPLIFIER WITH ARIABLE GAIN IN 8-PIN DIP/SO OUT 1/2MAX478 OUT = (1-2) (1 + R1 + 2 R1 ) R2 R3 OUTD IND- IND+ - INC+ INC- OUTC OUTA INA- INA+ + INB+ INB- OUTB 1 2 3 4 5 6 7 A D MAX479 B C DIP/SO 14 13 12 11 1 9 8 Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-8-998-88. For small orders, phone 1-8-835-8769.
ABSOLUTE MAXIMUM RATINGS Supply oltage...±22 Differential Input oltage...±3 Input oltage...equal to Positive Supply oltage...5 Below Negative Supply oltage Output Short-Circuit Duration...Continuous Continuous Power Dissipation (T A = +7 C): 8-Pin Plastic DIP (derate 9.9mW/ C above +7 C)..... 727mW 14-Pin Plastic DIP (derate 1.mW/ C above +7 C).. 8mW 14-Pin Wide SO (derate 9.52mW/ C above +7 C)... 762mW ELECTRICAL CHARACTERISTICS: 5 ( S = 5,, CM =.1, O = 1.4,, unless otherwise noted.) Operating Temperature Ranges: MAX47_ACP_/C... C to +7 C MAX47_E...-4 C to +85 C Storage Temperature Range...-65 C to +15 C Lead Temperature (soldering, 1sec)...+3 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. Input Offset oltage OS MAX478AC MAX479AC MAX478C/E MAX479C/E MAX478ACP/CP/EP 3 7 4 12 MAX479ACP/CP/EP 35 4 15 MAX478CS/ES 8 18 MAX479CS/ES 9 25 µ Long-Term Input Offset- oltage Stability OS Time.5.6 µ/mo. Input Offset Current I OS.5.25.5.35 na Input Bias Current I B 3 5 3 6 na Input Noise oltage e n.1hz to 1Hz (Note 1).9 2..9 µ p-p Input Noise oltage fo = 1Hz (Note 1) 5 75 5 n/ Hz Density fo = Hz (Note 1) 49 65 49 Input Noise Current i n.1hz to 1Hz (Note 1) 1.5 2.5 1.5 pa p-p Input Noise Current Density fo = 1Hz (Note 1).3.7.3 fo = Hz.1.1 Differential mode (Note 1).8 2..6 2. Input Resistance R IN Common mode 12 12 Upper limit 3.5 3.9 3.5 3.9 Input oltage Range IN (CM) Lower limit -.3 -.3 pa/ Hz CMRR CM = to 3.5 93 13 9 12 db PSRR S = 2.2 to 12 94 14 92 14 db O =.3 to 4, no load Large-Signal oltage Gain A OL (Note 1) 14 7 11 7 O =.3 to 3.5, R L = 5kΩ 8 2 7 2 GΩ /m 2
ELECTRICAL CHARACTERISTICS: 5 (continued) ( S = 5,, CM =.1, O = 1.4,, unless otherwise noted.) Output oltage Swing OUT MAX478AC MAX479AC MAX478C/E MAX479C/E Output low, no load 6.5 9. 6.5 9. Output low, 2kΩ to GND.2.6.2.6 Output low, I SINK = µa 12 16 12 16 Output high, no load 4.2 4.4 4.2 4.4 Output high, 2kΩ to GND 3.5 3.8 3.5 3.8 Slew Rate SR A = +1, C L = 1pF (Note 1).13.25.13.25 /µs Gain-Bandwidth Product GBW f O 5kHz 6 6 khz Supply Current per 13 18 14 21 I S Amplifier S = ±1.5, O = 12 17 13 2 m µa Channel Separation IN = 3, R L = 1kΩ 13 13 db Minimum Supply oltage S (Note 2) 2. 2.2 2. 2.2 ELECTRICAL CHARACTERISTICS: 5 ( S = 5,, CM =.1, O = 1.4, T A = C to +7 C, unless otherwise noted.) MAX478AC MAX479AC MAX478C MAX479C MAX478ACP/CP 5 17 65 25 Input Offset oltage OS MAX479ACP/CP 6 2 7 29 MAX478CS 12 3 µ MAX479CS 13 4 Input Offset oltage Drift OS MAX47_ACP/CP (Note 1).5 2.2.6 3. T MAX47_CS (Note 1).8 4.5 µ/ C Input Offset Current I OS.6.35.6.5 na Input Bias Current I B 3 6 3 7 na CMRR CM = to 3.4 9 11 86 db PSRR S = 2.5 to 12 9 12 88 12 db Large-Signal O =.5 to 4, no load (Note 1) 15 5 8 5 A OL oltage Gain O =.5 to 3.5, R L = 5kΩ 55 16 45 16 /m Output low, no load 8 11 8 11 m Output low, I SINK = µa 14 19 14 19 Output oltage Swing OUT Output high, no load 4.1 4.3 4.1 4.3 Output high, 2kΩ to GND 3.3 3.8 3.3 3.8 Supply Current per Amplifier I S 14 21 15 24 µa 3
ELECTRICAL CHARACTERISTICS: 5 ( S = 5,, CM =.1, O = 1.4, T A = -4 C to +85 C, unless otherwise noted.) MAX478EP MAX479EP MAX478ES MAX479ES Input Offset oltage OS MAX478 8 315 15 4 MAX479 8 345 16 53 Input Offset oltage Drift OS T (Note 1).6 3..8 4.5 µ/ C Input Offset Current I OS.7.7.7.7 na Input Bias Current I B 4 8 4 8 na CMRR CM =.5 to 3.2 84 98 84 98 db Large-Signal oltage Gain PSRR S = 3. to 12 86 86 db O =.5 to 4, no load (Note 1) 55 35 55 35 A OL O =.5 to 3.5, R L = 5kΩ 35 13 35 13 Output low, no load 9 13 9 13 m Output low, I SINK = µa 16 22 16 22 Output oltage Swing OUT Output high, no load 3.9 4.2 3.9 4.2 Output high, 2kΩ to GND 3. 3.7 3. 3.7 Supply Current per Amplifier I S 15 27 15 27 µa µ /m 4
ELECTRICAL CHARACTERISTICS: 3 ( S = 3,, CM =.1, O =.8,, unless otherwise noted.) Input Offset oltage MAX478AC MAX479AC MAX478C/E MAX479C/E 9 27 MAX479CS/ES Input Offset Current I OS.5.5 na Input Bias Current I B 3 3 na OS MAX478ACP/CP/EP 3 9 4 14 MAX479ACP/CP/EP 35 12 4 17 MAX478CS/ES 8 2 Input Noise oltage e N.1Hz to 1Hz 1. 1. µ p-p Upper limit 1.7 1.9 1.7 1.9 Input oltage Range IN (CM) Lower limit -.3 -.3 CMRR CM = to 1.7 93 13 9 12 db PSRR S = 2.2 to 12 94 14 92 14 db µ Large-Signal oltage Gain Output oltage Swing O =.3 to 2, no load 6 6 A OL (Note 1) OUT O =.3 to 1.5, R L = 5kΩ 3 18 3 18 Output low, no load 6 9 6 9 Output low, 2kΩ to GND.2.6.2.6 Output high, no load 2.2 2.4 2.2 2.4 Output high, 2kΩ to GND 1.8 2. 1.8 2. Gain-Bandwidth Product GBW f O 5kHz 5 5 khz Supply Current per Amplifier I S 12 17 13 2 µa 2.2 2.2 Minimum Supply oltage S With 3µ OS degradation 1.7 1.7 /m m 5
ELECTRICAL CHARACTERISTICS: ±15 (,, unless otherwise noted.) Input Offset Current I OS MAX478AC MAX479AC MAX478C/E MAX479C/E Input Offset oltage OS 8 35 48 µ Input Bias Current I B 3 5 3 6 na Upper limit 13.5 13.9 13.5 13.9 Input oltage Range IN (CM) Lower limit -15. -15.3-15. -15.3 CMRR CM = +13.5, -15 97 16 94 16 db Large-Signal oltage Gain.5.25.5.35 na PSRR S = 5, to ±15 96 112 94 112 db O = ±1, R L = 5kΩ 3 12 25 A OL O = ±1, no load 6 25 4 25 R L = 5kΩ ±13. ±14.2 ±13. ±14.2 Output oltage Swing OUT R L = 2kΩ ±11. ±12.7 ±11. ±12.7 Slew Rate SR A = +1, C L = 15pF.2.4.2.4 /µs Gain-Bandwidth Product GBW f O 5kHz 85 85 khz I S Supply Current per Amplifer 16 21 17 25 µa /m 6
ELECTRICAL CHARACTERISTICS: ±15 (, T A = C to +7 C, unless otherwise noted.) MAX478AC MAX479AC MAX478C MAX479C Input Offset oltage OS 48 13 66 Input Offset-oltage Drift OS MAX47_ACP/CP (Note 1).6 2.8.7 4. T MAX47_CS (Note 1).9 5.5 Input Offset Current I OS.6.35.6.35 na Input Bias Current I B 3 6 3 7 na Large-Signal oltage Gain µ/ C A OL O = ±1, R L = 5kΩ 2 8 15 75 /m CMRR CM = +13, -15 94 14 91 14 db PSRR S = 5, to ±15 93 11 91 11 db µ Output oltage Swing OUT R L = 5kΩ ±11. ±13.5 ±11. ±13.5 Supply Current per Amplifer I S 17 24 18 28 µa 7
ELECTRICAL CHARACTERISTICS: ±15 (, T A = -4 C to +85 C, unless otherwise noted.) Input Offset oltage Input Offset-oltage Drift Input Offset Current Input Bias Current Large-Signal oltage Gain OS OS T I OS I B MAX478EP MAX479EP MAX478ES MAX479ES 13 74 13 74 (Note 1).7 4..9 5.5 CMRR CM = +13, -14.9 88 13 88 13 db µ/ C.7.7.7.7 na A OL O = ±1, R L = 5kΩ 5 5 /m PSRR S = 5, to ±15 88 19 88 19 db µ 4 8 4 8 na Output oltage Swing OUT R L = 5kΩ ±11. ±13.5 ±11. ±13.5 Supply Current per Amplifer I S 19 3 19 3 µa Note 1: Note 2: Guaranteed by design. Power-supply rejection ratio is measured at the minimum supply voltage. The op amps actually work at 1.7 supply, but with additional input offset-voltage skew. 8
Typical Operating Characteristics SUPPLY CURRENT PER AMPLIFIER (µa) 2 18 16 14 12 SUPPLY CURRENT vs. TEMPERATURE S = 5, S = ±1.5 1-5 -25 25 5 75 TEMPERATURE ( C) OFFSET-OLTAGE SHIFT (µ) - -2-3 -4-5 MINIMUM SUPPLY OLTAGE +85 C NON-FUNCTIONAL 1 2 +25 C -4 C POSITIE SUPPLY OLTAGE () 3 OLTAGE GAIN (db) 14 12 8 6 4 2 OLTAGE GAIN vs. FREQUENCY S = 5, -2.1.1 1 1k k FREQUENCY (Hz) OLTAGE GAIN (db) OLTAGE GAIN (/) 3 2 1-1 1k 1M 1M k GAIN 5, S = 5,, GAIN, PHASE vs. FREQUENCY GAIN ±15 k PHASE ±15 FREQUENCY (Hz) PHASE 5, OLTAGE GAIN vs. LOAD RESISTANCE, S = 5,, T A = +85 C 8 12 16 2 24 1M PHASE SHIFT (DEGREES) CMRR (db) OERSHOOT (%) 12 8 4 12 8 6 4 2 COMMON-MODE REJECTION RATIO vs. FREQUENCY S = 5, 1 1 1k 1k k FREQUENCY (Hz) CAPACITIE LOAD HANDLING S = 5, A = +1 A = +5 A = +1 PSRR (db) SATURATION OLTAGE (m) 12 8 4 1 1 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY NEGATIE SUPPLY POSITIE SUPPLY S = ±2.5 + 1 p-p SINE WAE.1 1 1 1k 1k k FREQUENCY (Hz) S = 5, OUTPUT SATURATION vs. TEMPERATURE NO LOAD I SINK = 1mA I SINK = µa I SINK = 1µA 1kΩ TO GROUND 2kΩ TO GROUND 1k 1k k 1M LOAD RESISTANCE TO GROUND (Ω) 1M 1 CAPACITIE LOAD (pf) 1,.1-5 -25 25 5 75 TEMPERATURE ( C) 9
Typical Operating Characteristics (continued) OLTAGE NOISE DENSITY (n/ Hz) CURRENT NOISE DENSITY (fa/ Hz) 3 3 NOISE SPECTRUM CURRENT NOISE 1/f CORNER.5Hz 1.1 1 1 1k FREQUENCY (Hz) S = ±2.5 OLTAGE NOISE SHORT-CIRCUIT CURRENT (ma) SINKING SOURCING 2 1-1 -2-3 SHORT-CIRCUIT CURRENT 1 S = 5, S = ±2.5 S = ±2.5 TIME FROM OUTPUT SHORT TO GROUND (MINUTES) 2 INPUT OFFSET CURRENT (pa) INPUT BIAS CURRENT (na) 75 5 25-2.5-3. -3.5-4. -5 INPUT BIAS AND OFFSET CURRENT vs. TEMPERATURE S = 5, I OS -25 25 5 75 TEMPERATURE ( C) I B LARGE-SIGNAL TRANSIENT RESPONSE LARGE-SIGNAL TRANSIENT RESPONSE S = 5, SMALL-SIGNAL TRANSIENT RESPONSE S = ±2.5 OUTPUT OLTAGE (5/div) OUTPUT OLTAGE (1/div) 2 OUTPUT OLTAGE (2m/div) TIME (5µs/div) A = +1, C L = 15pF TIME (µs/div) A = +1, C L = 15pF TIME (2µs/div) A = +1, C L = 15pF SMALL-SIGNAL TRANSIENT RESPONSE S = 5, SMALL-SIGNAL TRANSIENT RESPONSE OUTPUT OLTAGE (2m/div) m OUTPUT OLTAGE (2m/div) TIME (2µs/div) A = +1, C L = 15pF TIME (2µs/div) A = +1, C L = 15pF 1
IN+ R1 Typical Application Circuit 1/4MAX479 1/4MAX479 RG 1M 2k R2 1M R1 1M R2 1M R3 9.1M 1/4MAX479 R3 9.1M GAIN = (1 + 2R1 ) ( R3 ) = FOR ALUES SHOWN RG R2 LOW-POWER INSTRUMENTATION AMPLIFIER OUTPUT Chip Topograqhy INA+ OUTA + OUTB IN- INA- INB-.111" (2.82mm) INB+ - +.79" (2.1mm) Package Information SOICN.EPS 11
Package Information (continued) PDIPN.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. 12 Maxim Integrated Products, 12 San Gabriel Drive, Sunnyvale, CA 9486 48-737-76 1998 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.