Texas Instruments INA250A4PW

Overview

INA250A4PW from Texas Instruments is a bidirectional, precision current-sense amplifier with an integrated 2 mΩ shunt resistor, delivering 2 V/A gain, ±15 A continuous sensing capability at –40°C to 85°C, and 108–118 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 space-constrained, calibrated, low-drift measurement is critical.

For engineers reviewing the INA250A4PW datasheet, INA250A4PW pinout, INA250A4PW application, or INA250A4PW equivalent, this page delivers verified package mapping (TSSOP-16), confirmed bidirectional operation via REF pin biasing, validated 2 V/A system gain with ±0.75% total error over temperature, and real-world alternatives for current-sense amplifier replacement in telecom and solar inverter designs.

Technical Context

The INA250A4PW implements a zero-drift, 36-V common-mode input amplifier paired with a laser-trimmed 2 mΩ internal shunt resistor, enabling RTI offset current as low as ±20 mA and CMRR up to 118 dB. Its Kelvin-connected SH+ and SH– terminals isolate sense path resistance from load current paths, eliminating PCB trace resistance errors.

It operates from 2.7 V to 36 V supply, draws ≤300 µA quiescent current, and supports bidirectional sensing by externally biasing the REF pin between 0 V and VS (≤18 V). Output swing reaches within 25 mV of GND and 0.1 V below VS at 10 kΩ load, supporting direct ADC interfacing without level-shifting.

Key Specifications

Pinout & Package

TSSOP-16 package (5.00 mm × 6.40 mm) with exposed thermal pad; optimized for high-current Kelvin routing and thermal dissipation in compact PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA250A4PW, INA240A4D offers higher bandwidth but demands careful external shunt integration, while MAX40056ASA+ extends common-mode range and speed at the cost of requiring a separate precision resistor and more complex layout-neither is pin-compatible, and both increase BOM count and calibration burden.

Availability

INA250A4PW is available at Aetrix Electronics and suitable for server power management, telecom rectifier monitoring, solar inverter DC-link sensing, industrial motor drive protection, and test equipment requiring stable component supply and long-term production continuity.

Supply support for INA250A4PW 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 chain and power management ICs.

The INA250 family was designed specifically for high-accuracy, space-constrained current sensing in power conversion systems-integrating shunt and amplifier to eliminate layout-induced errors and reduce calibration overhead in servers, telecom, and renewable energy applications.

FAQ

What is the maximum continuous current rating for the INA250A4PW at 125°C ambient?

The INA250A4PW supports ±10 A continuous current at 125°C ambient temperature, as specified in Figure 7-1 of the datasheet. At lower temperatures (e.g., 85°C), it handles ±15 A continuously. This derating accounts for package thermal resistance (RθJA = 104.4°C/W) and internal shunt self-heating. Proper PCB copper area and airflow are required to maintain safe junction temperature below 150°C.

Can the INA250A4PW measure bidirectional current without a dual supply?

Yes, the INA250A4PW measures bidirectional current using a single 2.7–36 V supply by applying a mid-rail reference voltage (e.g., 2.5 V) to the REF pin. With 2 V/A gain, ±10 A produces ±20 V output centered at the REF voltage-so 2.5 V REF yields 0.5 V to 4.5 V output for ±10 A. This eliminates need for dual supplies or level shifters in microcontroller ADC interfaces.

How does the integrated shunt resistor in the INA250A4PW differ from using a discrete 2 mΩ resistor?

The INA250A4PW's integrated 2 mΩ shunt is laser-trimmed and factory-matched to its amplifier, achieving ±0.1% tolerance and 10 ppm/°C tempco-far tighter than typical discrete resistors. Using it standalone degrades tolerance to ~5%. The monolithic Kelvin structure also guarantees optimal layout, eliminating trace resistance errors that plague discrete implementations in high-precision applications.

What is the output voltage swing limitation of the INA250A4PW at 5 V supply?

At VS = 5 V, the INA250A4PW output swings from (GND + 25 mV) to (VS – 0.1 V), i.e., 25 mV to 4.9 V into a 10 kΩ load. This 4.875 V span supports 2.4375 V full-scale for ±10 A (2 V/A), leaving margin for REF biasing. Driving capacitive loads >1 nF may cause instability; a series 10 Ω resistor is recommended for >100 pF loads.

Is the INA250A4PW RoHS-compliant and qualified for automotive use?

The INA250A4PW is RoHS-compliant and rated for –40°C to 125°C operation, but it is not AEC-Q200 qualified. It is intended for industrial, telecom, and computing applications-not automotive safety-critical systems. For automotive-grade equivalents, consider TI's INA229-Q1 or similar Q1-series devices with full AEC-Q200 certification and extended reliability testing.