INA121 datasheet pdf

1 ® INA121 International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111 Internet: http://www.burr-brown.com/ • FAXLine: (800) 548-6133 (US/Canada Only) • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132 ® INA121 INA121 INA121 ©1997 Burr-Brown CorporationPDS-1412APrinted in U.S.A. May, 1998 FEATURES lLOW BIAS CURRENT: ±4pA lLOW QUIESCENT CURRENT: ±450μA lLOW INPUT OFFSET VOLTAGE: ±200μV lLOW INPUT OFFSET DRIFT: ±2μV/°C lLOW INPUT NOISE: 20nV/√Hz at f = 1kHz (G =100) lHIGH CMR: 106dB lWIDE SUPPLY RANGE: ±2.25V to ±18V lLOW NONLINEARITY ERROR: 0.001% max lINPUT PROTECTION TO ±40V l8-PIN DIP AND SO-8 SURFACE MOUNT FET-Input, Low Power INSTRUMENTATION AMPLIFIER DESCRIPTION The INA121 is a FET-input, low power instrumenta- tion amplifier offering excellent accuracy. Its versatile three-op amp design and very small size make it ideal for a variety of general purpose applications. Low bias current (±4pA) allows use with high impedance sources. Gain can be set from 1V to 10,000V/V with a single external resistor. Internal input protection can with- stand up to ±40V without damage. The INA121 is laser-trimmed for very low offset voltage (±200μV), low offset drift (±2μV/°C), and high common-mode rejection (106dB at G = 100). It operates on power supplies as low as ±2.25V (+4.5V), allowing use in battery operated and single 5V sys- tems. Quiescent current is only 450μA. Package options include 8-pin plastic DIP and SO-8 surface mount. All are specified for the –40°C to +85°C industrial temperature range. APPLICATIONS lLOW-LEVEL TRANSDUCER AMPLIFIERS Bridge, RTD, Thermocouple lPHYSIOLOGICAL AMPLIFIERS ECG, EEG, EMG, Respiratory lHIGH IMPEDANCE TRANSDUCERS lCAPACITIVE SENSORS lMULTI-CHANNEL DATA ACQUISITION lPORTABLE, BATTERY OPERATED SYSTEMS lGENERAL PURPOSE INSTRUMENTATION A 1 A 2 A 3 6 40kΩ40kΩ 40kΩ40kΩ 7 4 3 8 1 2 V IN V IN R G V+ V– INA121 Ref V O G = 1 + 50kΩ R G – + 5 Over-Voltage Protection 25kΩ 25kΩ Over-Voltage Protection