FEATURES

LOW BIAS CURRENT: ±4pA

LOW QUIESCENT CURRENT: ±450mA

LOW INPUT OFFSET VOLTAGE: ±200mV

LOW INPUT OFFSET DRIFT: ±2mV/°C

LOW INPUT NOISE:

20nV/?Hz at f = 1kHz (G =100)

HIGH CMR: 106dB

WIDE SUPPLY RANGE: ±2.25V to ±18V

LOW NONLINEARITY ERROR: 0.001% max

INPUT PROTECTION TO ±40V

8-PIN DIP AND SO-8 SURFACE MOUNT

APPLICATIONS

LOW-LEVEL TRANSDUCER AMPLIFIERS

Bridge, RTD, Thermocouple

PHYSIOLOGICAL AMPLIFIERS

ECG, EEG, EMG, Respiratory

HIGH IMPEDANCE TRANSDUCERS

CAPACITIVE SENSORS

MULTI-CHANNEL DATA ACQUISITION

PORTABLE, BATTERY OPERATED SYSTEMS

GENERAL PURPOSE INSTRUMENTATION

DESCRIPTION

The INA121 is a FET-input, low power instrumentation

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 withstand

up to ±40V without damage.

The INA121 is laser-trimmed for very low offset

voltage (±200mV), low offset drift (±2mV/°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 systems.

Quiescent current is only 450mA.

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.