INA122P Single-Supply Micropower Instrumentation Amplifier DIP-8 (INA122P IC)

The INA122P is a precision instrumentation amplifier designed for accurate, low-noise differential signal acquisition, especially in portable and battery-operated systems. Housed in a standard 8-pin DIP package, it features a unique two-op-amp design that allows for an exceptionally low quiescent current of just 60uA. Unlike many traditional instrumentation amplifiers, the INA122 is optimized for single-supply operation (down to 2.2V), with an input common-mode range that extends below the negative rail, making it ideal for interfacing with sensors in low-voltage environments.

This IC is a staple in India for industrial field transmitters, portable medical equipment like ECGs, and bridge sensor amplification. Its ability to provide high gain (up to 10,000x) with a single external resistor while maintaining high common-mode rejection makes it a versatile tool for precision data acquisition.

Key Features

• Ultra-Low Power: Micropower operation with only 60uA quiescent current, perfect for long battery life.
• Wide Supply Range: Operates on single or dual supplies ranging from 2.2V to 36V.
• Rail-to-Rail Output: Maximizes dynamic range by swinging close to the supply rails.
• High Precision: Features low offset voltage (250uV max) and low offset drift (3uV/C).
• Flexible Gain: Easily adjustable gain from 5 to 10,000 using one external resistor (RG).
• Excellent Noise Performance: Low input noise density of 60nV/rtHz for clear signal recovery.
• Input Protection: Internal diodes protect inputs against overvoltage conditions.

Specifications

• IC Type: Instrumentation Amplifier
• Number of Channels: 1
• Supply Voltage: 2.2V to 36V (Single) / +/-0.9V to +/-18V (Dual)
• 3dB Bandwidth: 120 kHz
• Slew Rate: 0.16 V/us
• Common-Mode Rejection (CMRR): 90dB (Typical)
• Input Bias Current: 25nA (Max)
• Package Type: PDIP-8 (Through-Hole)
• Operating Temperature: -40 to +85 degrees Celsius

Pinout Configuration

• Pin 1 (RG): Gain Set Resistor Connection 1
• Pin 2 (-IN): Inverting Input
• Pin 3 (+IN): Non-Inverting Input
• Pin 4 (V-): Negative Supply (or Ground for single-supply)
• Pin 5 (REF): Reference Input (must be low impedance)
• Pin 6 (OUT): Amplifier Output
• Pin 7 (V+): Positive Supply
• Pin 8 (RG): Gain Set Resistor Connection 2