Texas Instruments INA250A3PWR

Overview

INA250A3PWR from Texas Instruments is a bidirectional, precision current-sense amplifier with an integrated 2 mΩ shunt resistor, 800 mV/A gain, ±15 A continuous current capability at –40°C to 85°C, and 106–114 dB common-mode rejection over –40°C to 125°C. It enables high-accuracy, Kelvin-connected current monitoring in power supplies and server PMBus rails where low drift and system-calibrated accuracy are critical.

For engineers reviewing the INA250A3PWR datasheet, INA250A3PWR pinout, INA250A3PWR application, or INA250A3PWR equivalent, key selection considerations include its integrated shunt tolerance (0.1% max), RTI offset current (±5 mA max), temperature coefficient (10 ppm/°C from 0°C to 125°C), and TSSOP-16 package thermal performance (R_θJA = 104.4°C/W).

Technical Context

The INA250A3PWR implements a zero-drift, 36-V common-mode input amplifier paired with a monolithically integrated 2 mΩ Kelvin shunt, enabling bidirectional sensing without external layout compromises. Its gain of 800 mV/A is factory-trimmed to ensure system-level calibration across temperature.

It supports unidirectional or bidirectional operation via the REF pin (0 V to VS, up to 18 V), and features ultra-low drift: shunt TC = 10 ppm/°C (0°C–125°C), system gain error drift = 45 ppm/°C, and CMRR ≥106 dB across full operating temperature.

Key Specifications

Pinout & Package

Packaged in a 16-pin TSSOP (PW), the INA250A3PWR uses a thermally enhanced layout with three GND pins (6, 8, 11) and dedicated Kelvin sense terminals (SH+, SH–) to preserve shunt accuracy. The package measures 5.00 mm × 6.40 mm and supports PCB copper planes for 15 A continuous conduction at ≤85°C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision current-sense amplifier applications.

Compared with INA240A3PWR and MAX40086ATA+T, the INA250A3PWR uniquely delivers factory-matched 2 mΩ shunt + amplifier calibration in a single TSSOP-16 package, achieving ±0.3% system gain error without layout-dependent tuning-critical for volume-manufactured power supplies and servers.

Availability

INA250A3PWR is available at Aetrix Electronics and suitable for power supplies, server PMBus telemetry, and solar inverter string monitoring requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for INA250A3PWR 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 is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision signal conditioning and power management ICs.

The INA250 family was designed specifically for high-accuracy, integrated current sensing in industrial, computing, and renewable energy systems-replacing discrete shunt + op-amp solutions with guaranteed system-level calibration and thermal stability.

FAQ

What is the maximum continuous current rating for the INA250A3PWR?

The INA250A3PWR supports ±15 A continuous current at ambient temperatures up to 85°C with 1-oz copper planes and no forced airflow. At 125°C ambient, the rating derates to ±10 A, as specified in Figure 7-1 of the SBOS511C datasheet. This rating applies to the total package resistance (4.5 mΩ), not just the integrated 2 mΩ shunt.

Does the INA250A3PWR require external calibration to achieve its 0.3% system gain accuracy?

No. The INA250A3PWR achieves ±0.3% system gain error (including both shunt tolerance and amplifier gain error) without external calibration. This accuracy is factory-trimmed and guaranteed over –40°C to 125°C. The integrated 2 mΩ shunt and amplifier are matched during production to deliver calibrated performance out-of-box.

Can the INA250A3PWR measure bidirectional current, and how is it configured?

Yes. The INA250A3PWR supports bidirectional current sensing by applying a reference voltage to the REF pin. For example, connecting REF to 2.5 V sets zero-current output to 2.5 V; positive current raises OUT above 2.5 V, and negative current pulls it below. The REF voltage must stay between 0 V and VS (≤18 V) per datasheet Section 6.5.

What is the purpose of the SH+ and SH– pins on the INA250A3PWR?

The SH+ and SH– pins provide Kelvin connections to the internal 2 mΩ shunt resistor. They must be connected directly to VIN+ and VIN– respectively to enable accurate 4-wire sensing and eliminate errors from PCB trace resistance. These pins are not intended for external routing or standalone shunt use-the device is calibrated only when SH+/SH– are used with the internal amplifier.

How does the INA250A3PWR's common-mode rejection compare to discrete alternatives?

The INA250A3PWR delivers 106–114 dB CMRR over –40°C to 125°C-significantly higher than typical discrete op-amp + shunt solutions (<90 dB). This is achieved through monolithic integration of the shunt and amplifier, eliminating inter-component mismatches and layout-induced imbalances that degrade CMRR in discrete designs.