Texas Instruments INA254A3IPWAR

Overview

INA254A3IPWAR from Texas Instruments is a high-voltage, bidirectional current-shunt monitor integrating a precision 400-µΩ shunt resistor and zero-drift amplifier in a single 24-pin HTSSOP package. It delivers 75 mV/A gain, ±50 A continuous current sensing from –40°C to +85°C, 0.5% system gain error (max), and operates over –4 V to +80 V common-mode range - enabling accurate real-time current measurement in high-side motor-drive and solenoid control circuits.

For engineers reviewing the INA254A3IPWAR datasheet, INA254A3IPWAR pinout, INA254A3IPWAR application, or INA254A3IPWAR equivalent, this page provides verified technical context, validated pin functions, confirmed thermal and PWM rejection performance, and direct alternative part comparisons for high-accuracy, high-voltage current sensing designs.

Technical Context

The INA254A3IPWAR implements a Kelvin-connected integrated shunt with 400-µΩ nominal resistance and 10 ppm/°C drift (0°C–125°C), paired with a zero-drift chopped amplifier achieving DC CMRR >120 dB and 90 dB AC CMRR at 50 kHz. Its enhanced PWM rejection circuitry suppresses large dv/dt transients without bandwidth expansion, preserving signal fidelity during switching events.

This device uses dual reference inputs (REF1/REF2) to support bidirectional operation with user-defined zero-current output offset, and features internal 2 nH shunt inductance and 1 mΩ total package resistance - both critical for minimizing phase shift and self-heating in high-current, high-frequency applications like 48-V motor controls and DC/DC converters.

Key Specifications

Pinout & Package

INA254A3IPWAR is housed in a 24-pin HTSSOP package (9.50 mm × 4.40 mm body size) with exposed thermal pad. Pin layout follows TI's PWA package standard, optimized for Kelvin sensing and thermal management in high-current PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage bidirectional current sensing applications.

Compared with INA254A3IPWAR, INA240A3QDR requires careful external shunt selection and layout to approach similar accuracy, while ACS724LMATR-50AB-T trades isolation for reduced bandwidth and higher temperature-induced error - making INA254A3IPWAR optimal for compact, high-speed, high-accuracy 48-V system current sensing where integration and thermal stability are critical.

Availability

INA254A3IPWAR is available at Aetrix Electronics and suitable for 48-V motor controls, DC/DC converters, and medical cordless tools requiring stable component supply, long-term production continuity, and guaranteed traceable sourcing.

Supply support for INA254A3IPWAR 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 INA254 product line was designed specifically for high-accuracy, high-voltage bidirectional current sensing in industrial motor drives, energy-efficient power conversion, and safety-critical portable equipment - integrating shunt and amplifier to eliminate system-level calibration.

FAQ

What is the maximum continuous current rating for INA254A3IPWAR at +125°C ambient?

The INA254A3IPWAR supports ±30 A continuous current at +125°C ambient temperature, as specified in the thermal derating curve (Figure 8-1). This limitation arises from package thermal resistance (RθJA = 19.4°C/W) and total 1 mΩ package resistance dissipating heat under load. At +85°C ambient, it sustains ±50 A continuously when mounted on 2-oz copper planes with no forced airflow. The device junction temperature must remain ≤150°C for reliable operation.

Can INA254A3IPWAR be used for unidirectional current sensing only?

Yes, INA254A3IPWAR supports unidirectional operation by connecting REF2 to GND and REF1 to a fixed bias voltage (e.g., 0.5 V), setting the zero-current output to a non-midrail value. Its bidirectional architecture allows flexible configuration - unlike dedicated unidirectional monitors, it retains full accuracy and offset control across the entire ±50 A range even when used unidirectionally, with no performance penalty.

How does the integrated 400-µΩ shunt differ from using a discrete shunt resistor with a separate amplifier?

The INA254A3IPWAR's integrated 400-µΩ shunt is Kelvin-connected, thermally coupled to the amplifier die, and factory-matched to achieve ±0.5% system gain error - impossible with discrete solutions due to thermal gradients, trace resistance, and component tolerances. Using an external shunt introduces ≥1% additional error from layout parasitics and mismatch, while the integrated design eliminates solder-joint resistance, improves PWM rejection, and reduces PCB area by >60%.

What is the purpose of the RES pin on INA254A3IPWAR?

The RES pin (Pin 15) on INA254A3IPWAR is a reserved function pin that must be connected to GND per the datasheet. It is not internally connected to any active circuitry but serves as a thermal and mechanical anchor point in the HTSSOP package. Leaving it floating or connecting it to VS may cause undefined behavior or degrade thermal performance; grounding ensures proper package stress relief and ESD path integrity.

Does INA254A3IPWAR require external filtering for PWM noise suppression?

No, INA254A3IPWAR incorporates on-die enhanced PWM rejection circuitry that actively suppresses large dv/dt common-mode transients up to 100 V/µs without external RC filters. Its architecture achieves 90 dB AC CMRR at 50 kHz and minimal output ringing during PWM edge transitions - verified in Figure 7-28 through Figure 7-31. External filtering is optional only for ultra-low-noise applications beyond datasheet specifications.