Texas Instruments INA381A2QDGSRQ1

Overview

INA381A2QDGSRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive current-sense amplifier with integrated overcurrent comparator, designed for high-accuracy shunt-based current monitoring in systems with common-mode voltages up to +26 V. It delivers 50 V/V gain, ±150 µV max offset at 0 V common-mode, 1 µV/°C drift, and <10 µs total overcurrent response time. It is used in body control modules and ADAS domain controllers for real-time load protection.

For engineers reviewing the INA381A2QDGSRQ1 datasheet, INA381A2QDGSRQ1 pinout, INA381A2QDGSRQ1 application, or INA381A2QDGSRQ1 equivalent, key selection criteria include its 50 V/V fixed gain, –0.2 V to +26 V input common-mode range, open-drain ALERT with 50 mV hysteresis, transparent/latched mode control via RESET, and VSSOP-10 packaging for space-constrained automotive PCBs.

Technical Context

The INA381A2QDGSRQ1 integrates a zero-drift current-sense amplifier and a standalone comparator in a single die. Its amplifier uses chopper-stabilized architecture to achieve ≤150 µV offset at 0 V VCM and 1 µV/°C drift across –40°C to +125°C, enabling precise low-value shunt measurements. The comparator features 400 ns typical propagation delay, 50 mV hysteresis, and user-configurable threshold via CMPREF.

It operates from 2.7 V to 5.5 V supply, draws ≤350 µA quiescent current, and supports both high-side and low-side sensing due to its rail-to-rail input common-mode range independent of VS. The ALERT output is open-drain with internal latch/transparent mode selection via RESET pin logic level.

Key Specifications

Pinout & Package

INA381A2QDGSRQ1 is housed in a 10-pin VSSOP package (3.00 mm × 3.00 mm), thermally enhanced with exposed thermal pad connected to GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA381A2QDGSRQ1, INA240A2QDRQ1 extends common-mode range but adds design complexity, while MAX40056ATA+T offers improved precision in low-voltage domains but lacks automotive qualification and high-side capability - making INA381A2QDGSRQ1 optimal for cost-sensitive, space-constrained AEC-Q100-compliant 12-V/24-V systems.

Availability

INA381A2QDGSRQ1 is available at Aetrix Electronics and suitable for ADAS domain controllers, body control modules, and seat position systems requiring stable component supply across automotive production lifecycles.

Supply support for INA381A2QDGSRQ1 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 delivering analog and embedded processing solutions, with deep expertise in precision signal chain and automotive-grade IC design.

The INA381-Q1 product line is engineered specifically for automotive current sensing and overcurrent protection, targeting functional-safety-aware systems requiring integrated analog sensing and digital fault signaling in compact packages.

FAQ

What is the maximum common-mode voltage supported by the INA381A2QDGSRQ1?

The INA381A2QDGSRQ1 supports a common-mode input voltage range of –0.2 V to +26 V, independent of its 2.7–5.5 V supply voltage. This allows direct high-side sensing on 12-V and 24-V automotive battery rails without level-shifting circuitry. The device remains functional and undamaged even when the supply is removed while 26 V is present at the inputs.

How does the gain option of INA381A2QDGSRQ1 differ from other variants in the family?

The INA381A2QDGSRQ1 is factory-set to 50 V/V gain, distinct from INA381A1QDGSRQ1 (20 V/V), INA381A3QDGSRQ1 (100 V/V), and INA381A4QDGSRQ1 (200 V/V). This fixed gain determines the scaling between shunt voltage and VOUT, directly impacting resolution and dynamic range - for example, a 10-mΩ shunt yields 500 µV/mA at the output.

Can the INA381A2QDGSRQ1 operate in both high-side and low-side current sensing configurations?

Yes, the INA381A2QDGSRQ1 supports both high-side and low-side current sensing due to its –0.2 V to +26 V input common-mode range. In low-side configurations, IN– connects to ground and IN+ to the shunt's load side; in high-side configurations, IN+ connects to the battery rail and IN– to the shunt's load side - both valid without external components.

What is the function of the RESET pin on the INA381A2QDGSRQ1?

The RESET pin on the INA381A2QDGSRQ1 selects the ALERT output behavior: pulled low for transparent mode (ALERT follows input state in real time), or pulled high for latched mode (ALERT remains asserted until manually cleared). This enables flexible integration with either interrupt-driven or polled microcontroller firmware architectures.

Does the INA381A2QDGSRQ1 include built-in hysteresis for the comparator, and what is its value?

Yes, the INA381A2QDGSRQ1 includes 50 mV of internal hysteresis on its comparator to prevent oscillation near the overcurrent threshold. This hysteresis is fixed and not adjustable - when CMPIN exceeds CMPREF, ALERT asserts; it deasserts only after CMPIN falls below (CMPREF – 50 mV).