INA117P Precision Instrumentation Amplifier

Updated: 2026-08-26

Overview

The INA117P is a precision instrumentation amplifier that provides accurate amplification of differential signals in the presence of large common-mode voltages. Manufactured by Texas Instruments, it is widely used in industrial and medical applications where high accuracy and noise rejection are critical. The device operates over a wide power supply range and offers excellent linearity, making it suitable for applications such as strain gauge amplification, thermocouple signal conditioning, and medical instrumentation.

Structure and Working Principle

The INA117P consists of three operational amplifiers configured in an instrumentation amplifier topology. The input stage provides high input impedance and common-mode rejection, while the output stage delivers a single-ended output proportional to the differential input signal. Internal precision resistors are laser-trimmed to ensure high accuracy and temperature stability. The device maintains its performance across a wide temperature range, making it reliable for demanding environments.

Key Features

The INA117P offers a common-mode rejection ratio (CMRR) of 120dB (min), ensuring effective rejection of noise and interference. Its low offset voltage (50μV max) and low drift characteristics contribute to high measurement accuracy. The amplifier operates from ±4.5V to ±18V power supplies, accommodating a wide range of industrial voltage levels. It also features protection against overvoltage conditions on the inputs, enhancing system reliability.

Application Areas

Industrial applications include process control systems, data acquisition, and sensor signal conditioning. The INA117P is particularly useful for amplifying signals from strain gauges, pressure sensors, and other bridge-type transducers. In medical electronics, it finds use in patient monitoring equipment and diagnostic instruments where accurate signal amplification is crucial. The device's high CMRR makes it suitable for applications involving long cable runs or noisy environments.

Maintenance and Precautions

Proper PCB layout is essential when using the INA117P. Keep input traces short and symmetrical to maintain CMRR performance. Use ground planes and proper decoupling capacitors near the power supply pins. Avoid exposing the device to voltages beyond its absolute maximum ratings. For applications with potentially hazardous input voltages, consider adding external protection circuitry such as clamping diodes or current-limiting resistors.

B2B Procurement Guide

When sourcing INA117P amplifiers, verify the manufacturer's authenticity to avoid counterfeit components. Consider purchasing from authorized distributors or directly from Texas Instruments. For high-volume applications, discuss lead times and minimum order quantities with suppliers. Evaluate alternative packaging options (tube, reel, or tray) based on your production requirements. Request samples for testing before committing to large orders.