1 Features

1• Low offset voltage: 10 μV (typ), 35 μV (max)

• Gain drift: 5 ppm/°C (G = 1),

35 ppm/°C (G > 1) (max)

• Noise: 7 nV/√Hz

• Bandwidth: 4.7 MHz (G = 1), 290 kHz (G = 100)

• Stable with 1-nF capacitive loads

• Inputs protected up to ±40 V

• Common-mode rejection: 112 dB, G = 10 (min)

• Power supply rejection: 110 dB, G = 1 (min)

• Supply current: 650 μA (max)

• Supply range:

– Single-supply: 4.5 V to 36 V

– Dual-supply: ±2.25 V to ±18 V

• Specified temperature range: –40°C to +125°C

• Packages: 8-pin SOIC, VSSOP, and WSON

2 Applications

• Analog input module

• Flow transmitter

• Battery test

• LCD test

• Electrocardiogram (ECG)

• Surgical equipment

• Process analytics (pH, gas, concentration, force

and humidity)

3 Description

The INA821 is a high-precision instrumentation

amplifier that offers low power consumption and

operates over a wide single-supply or dual-supply

range. A single external resistor sets any gain from 1

to 10,000. The device has high precision as a result

of super-beta input transistors, which provide low

input offset voltage, offset voltage drift, input bias

current, and input voltage and current noise.

Additional circuitry protects the inputs against

overvoltage up to ±40 V.

The INA821 is optimized to provide a high commonmode

rejection ratio. At G = 1, the common-mode

rejection ratio exceeds 92 dB across the full input

common-mode range. The device is designed for lowvoltage

operation from a 4.5-V single supply, and

dual supplies up to ±18 V.

The INA821 is available in 8-pin SOIC, VSSOP, and

WSON packages, and is specified over the –40°C to

+125°C temperature range.