Texas Instruments INA2132U

Overview

INA2132U from Texas Instruments (formerly Burr-Brown) is a dual, low-power, unity-gain difference amplifier in SO-14 package, delivering ±0.05% max gain error, 90dB CMRR, and 160µA per amplifier quiescent current. It operates from single supply (2.7V to 36V) or dual supplies (±1.35V to ±18V), with input common-mode range extending beyond rails - ideal for precision current sensing and ground-loop elimination in battery-powered instrumentation.

For engineers reviewing the INA2132U datasheet, INA2132U pinout, INA2132U application, or INA2132U equivalent, key selection considerations include guaranteed rail-to-rail input common-mode operation down to V–, laser-trimmed resistor network accuracy, dual-channel independence, and specified performance over –40°C to +85°C industrial temperature range.

Technical Context

The INA2132U integrates two independent precision op amps with matched 40kΩ laser-trimmed thin-film resistor networks, enabling accurate unity-gain differential amplification without external precision resistors. Its internal architecture maintains high CMRR via TCR-matched resistors and extends input common-mode voltage to 2×(V–) and nearly 2×(V+) – 1V.

Each channel features rail-to-rail output swing (e.g., (V+) – 0.8V / (V–) + 0.15V at 10kΩ load), 300kHz small-signal bandwidth, and stable operation with up to 10nF capacitive load - supporting direct interface with ADCs, current-sense shunts, and level-shifting circuits without external compensation.

Key Specifications

Pinout & Package

INA2132U is housed in a 14-pin SOIC (SO-14, package drawing D), surface-mount package with 1.27mm pitch, JEDEC MS-012 compliant, RoHS-compliant (Green, NIPDAU finish), MSL Level-3 moisture sensitivity rating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar difference amplifier applications.

Compared with INA2132U, INA2133U provides higher fixed gain but sacrifices unity-gain accuracy, while INA132UA offers identical per-channel performance in half the footprint - both require schematic and layout changes, making INA2132U optimal for dual-channel, space-tolerant, unity-gain precision sensing.

Availability

INA2132U is available at Aetrix Electronics and suitable for high-reliability current sensing, industrial instrumentation front-ends, and battery management systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for INA2132U includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments acquired Burr-Brown in 2000 and maintains its precision analog portfolio, renowned for high-accuracy signal conditioning ICs used in test equipment, industrial automation, and medical devices.

The INA2132U belongs to TI's legacy difference amplifier product line, engineered specifically for cost-sensitive, low-power, high-CMRR applications where laser-trimmed resistor networks eliminate external component tolerance dependencies.

FAQ

What is the maximum common-mode voltage the INA2132U can handle with a +5V single supply?

The INA2132U supports a common-mode input range of –2.5V to +5.5V when operated from a +5V single supply. This is calculated as 2×(V–) to 2×((V+) – 1) – VREF, where V– = 0V and VREF = 0V yields –2.5V ≤ VCM ≤ +5.5V. This rail-extended range enables accurate sensing of signals referenced above ground - such as high-side shunt measurements - without external level shifting. The INA2132U maintains 90dB CMRR across this full range.

Can the INA2132U be used with a 3.3V supply, and what performance trade-offs occur?

Yes, the INA2132U operates from 2.7V to 36V single supply, including 3.3V. At 3.3V, the output swing reduces to approximately (V+) – 0.8V = +2.5V and (V–) + 0.15V = +0.15V (at 10kΩ load), compressing dynamic range. CMRR remains ≥80dB, and quiescent current stays near 160µA. However, offset voltage increases slightly (±500µV max vs ±250µV at ±15V), and small-signal bandwidth decreases marginally. The INA2132U remains fully functional for low-voltage portable instrumentation where these trade-offs are acceptable.

Why are pins 12 (Sense A) and 10 (Sense B) not intended for external connection?

Pins 12 and 10 connect to internal nodes of the laser-trimmed 40kΩ resistor network. Interchanging them with +In/–In pins (e.g., connecting external signal to Sense instead of +In) disrupts the precisely trimmed resistor ratios, degrading gain accuracy and CMRR below specification. The INA2132U datasheet explicitly warns against this. These pins exist solely for internal calibration - all external signals must connect only to +In/–In (pins 2/3 and 5/6) and Ref/Out (pins 14/13 and 8/9). Using Sense pins invalidates INA2132U performance guarantees.

Does the INA2132U support differential output configurations?

No, the INA2132U provides single-ended outputs only (pins 13 and 9). However, Figure 8 of the INA2132U datasheet demonstrates how two channels can be configured to generate complementary differential outputs: Channel A outputs V01 = V2 – V1, Channel B outputs V02 = V1 – V2, yielding V01 – V02 = 2(V2 – V1). This requires external summing or dedicated differential receiver stages. The INA2132U itself does not integrate differential output drivers or internal output phase inversion - all outputs are referenced to their respective Ref pins (14/8) and are inherently single-ended.

How does channel crosstalk affect simultaneous measurement in dual-channel applications?

At DC and low frequencies (<100Hz), channel crosstalk in the INA2132U is negligible (<0.04µV/V), ensuring truly independent operation for static measurements like battery cell monitoring. Above 1kHz, crosstalk rises due to capacitive coupling, reaching ~80dB at 100kHz. To maintain isolation, separate input traces for each channel, use grounded guard traces, and route differential pairs adjacently. The INA2132U's design minimizes crosstalk through fully independent bias circuitry - critical for dual-channel DAQ where one channel measures shunt current while the other reads temperature sensor output.