Texas Instruments INA381A4IDSGR

Overview

INA381A4IDSGR from Texas Instruments is a 26-V, high-speed current-sense amplifier with integrated comparator and fixed gain of 200 V/V, designed for overcurrent protection in high-side and low-side sensing applications. It operates from 2.7 V to 5.5 V supply, supports –0.2 V to +26 V common-mode input range, delivers <10 µs total overcurrent response time, and is qualified for –40°C to +125°C industrial operation.

For engineers reviewing the INA381A4IDSGR datasheet, INA381A4IDSGR pinout, INA381A4IDSGR application, or INA381A4IDSGR equivalent, this page provides verified functional context, validated WSON-8 package mapping, confirmed comparator hysteresis (50 mV), real-world alert propagation timing (<2 µs comparator-only), and precise gain-error drift (20 ppm/°C) - all critical for motor drive fault detection, server PSU monitoring, and cordless tool protection design.

Technical Context

The INA381A4IDSGR implements a zero-drift amplifier topology enabling ≤150 µV max offset at 0 V common-mode and ≤500 µV at 12 V, with 1 µV/°C drift over –40°C to +125°C. Its integrated open-drain comparator features 400 ns typical propagation delay, 50 mV hysteresis, and user-configurable transparent/latched alert modes via RESET pin.

This device performs simultaneous analog amplification (G = 200 V/V) and digital threshold comparison on the same die: VOUT feeds CMPIN directly or through external conditioning, while CMPREF accepts externally set reference voltage (e.g., REF3140). The architecture supports rail-to-rail output swing (VS – 0.05 V) and withstands 26 V input common-mode even with VS removed.

Key Specifications

Pinout & Package

The INA381A4IDSGR is packaged in an 8-pin WSON (DSG) with 2.00 mm × 2.00 mm body size and exposed thermal pad. Pin 1 is marked by a dot; the thermal pad must be soldered to PCB ground for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA240A4DRCR and MAX40056ATA+T, the INA381A4IDSGR uniquely integrates comparator hysteresis, delivers <10 µs total fault response, and maintains ≤500 µV offset at 12 V VCM - making it optimal for compact, cost-sensitive, high-reliability overcurrent detection where 26 V common-mode suffices.

Availability

INA381A4IDSGR is available at Aetrix Electronics and suitable for server PSU monitoring, BLDC motor drive protection, and cordless power tool battery management requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for INA381A4IDSGR 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 amplifiers and power management ICs.

The INA381 product line delivers integrated current-sense amplifiers with onboard comparators for rapid overcurrent detection in high-reliability power systems - targeting merchant server, industrial motor control, and portable power applications.

FAQ

What is the maximum common-mode voltage the INA381A4IDSGR can handle?

The INA381A4IDSGR supports a common-mode input voltage range of –0.2 V to +26 V, independent of its 2.7 V to 5.5 V supply voltage. This allows direct high-side sensing on 24-V rails without level-shifting. The device remains undamaged even when 26 V is applied to IN+/IN– with VS disconnected, per absolute maximum ratings.

Does the INA381A4IDSGR require external components to configure the comparator threshold?

Yes - the comparator threshold is set by the voltage applied to the CMPREF pin, which can be driven by a resistive divider from VS or an external precision reference like REF3140. No external hysteresis components are needed, as the INA381A4IDSGR integrates 50 mV hysteresis internally.

What is the total overcurrent detection latency of the INA381A4IDSGR?

The total system overcurrent protection response time of the INA381A4IDSGR is less than 10 µs. This includes amplifier settling time and comparator propagation delay. The comparator-only propagation delay is 400 ns typical, and large-signal alert response is under 2 µs, enabling fast coordination with gate drivers in motor or PSU fault paths.

Can the INA381A4IDSGR operate in both high-side and low-side current sensing configurations?

Yes - the INA381A4IDSGR supports both configurations. Its –0.2 V to +26 V common-mode range enables high-side sensing on positive rails, while its low 150 µV offset at 0 V VCM makes it ideal for low-side sensing where accuracy at near-ground voltages is critical, such as in battery protection circuits.

What package type and thermal characteristics does the INA381A4IDSGR use?

The INA381A4IDSGR uses the 8-pin WSON (DSG) package with 2.00 mm × 2.00 mm body size and exposed thermal pad. Its junction-to-board thermal resistance (RθJB) is 43.4°C/W, and junction-to-ambient (RθJA) is 77°C/W - requiring proper thermal pad soldering to PCB ground for reliable operation at full temperature range.