Texas Instruments INA241A4IDR

Overview

INA241A4IDR from Texas Instruments is an ultra-precise, bidirectional current sense amplifier optimized for high-voltage switching systems. It operates over −5V to 110V common-mode range, delivers 100V/V fixed gain, ±0.015% max gain error, ±10µV max input offset voltage, and 1.1MHz bandwidth - enabling accurate inline motor-phase current measurement in PWM-driven inverters.

For engineers reviewing the INA241A4IDR datasheet, INA241A4IDR pinout, INA241A4IDR application, or INA241A4IDR equivalent, this page provides verified technical context, validated pin functions, confirmed performance under fast common-mode transients (≤125kHz), and real-world implementation guidance for high-side/low-side sensing in industrial motion control.

Technical Context

The INA241A4IDR employs a zero-drift, multistage amplifier architecture with enhanced PWM rejection circuitry that holds output for 1µs during large ΔV/Δt common-mode transients-suppressing propagation of switching noise from motor gate drivers. Its input bias current remains constant (35µA typ) across −20V to 120V survival range, independent of V_CM.

It supports bidirectional sensing via dual reference inputs (REF1/REF2), allowing configurable output centering (e.g., mid-supply for ±I_SENSE). The 100V/V gain enables precise low-V_SENSE detection down to ±5mV full-scale while maintaining 8V/µs slew rate and 1µs 1% settling time - critical for overcurrent fault response in real-time motor protection.

Key Specifications

Pinout & Package

INA241A4IDR is packaged in SOIC-8 (D package), 4.9mm × 6mm body with standard 1.27mm pitch. Pin functions are identical across D, DDF, and DGK packages per TI SBOSA30D Rev D.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA240A4IDR and MAX40056ASA+T, the INA241A4IDR uniquely combines 110V common-mode capability, 125kHz PWM rejection, and programmable bidirectional output - making it the only option qualified for safety-critical motor phase current sensing in automotive-grade industrial drives.

Availability

INA241A4IDR is available at Aetrix Electronics and suitable for motor drives, solenoid control, injection molding machines, and cordless power tools requiring stable component supply, long-term production continuity, and guaranteed traceability.

Supply support for INA241A4IDR 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 high-reliability industrial ICs.

The INA241x product line was designed specifically for high-voltage, high-speed current sensing in PWM-controlled power stages - targeting motor control, energy storage, and automated industrial equipment where accuracy, transient immunity, and temperature stability are non-negotiable.

FAQ

What is the maximum common-mode voltage the INA241A4IDR can withstand continuously?

The INA241A4IDR operates continuously over −5V to 110V common-mode input range. Its survival rating extends to −20V to 120V, meaning it tolerates brief transients within that range without damage. This allows direct high-side sensing on 48V, 60V, and 80V industrial buses without external protection circuitry - a key advantage over legacy amplifiers limited to supply-rail-referenced ranges.

How does the enhanced PWM rejection in the INA241A4IDR improve motor control reliability?

The INA241A4IDR's enhanced PWM rejection blocks output disturbance during fast common-mode edges (up to 125kHz), holding the output steady for 1µs after each edge. This prevents false overcurrent readings during MOSFET switching in BLDC inverters - directly improving field-oriented control stability and eliminating nuisance trips in drone propeller speed control systems using the INA241A4IDR.

Can the INA241A4IDR measure bidirectional current without external components?

Yes. The INA241A4IDR supports true bidirectional sensing natively via its REF1 and REF2 pins: connecting REF1 to GND and REF2 to V_S centers the output at V_S/2, allowing positive and negative V_SENSE to produce outputs above and below mid-supply. No external op-amps, resistors, or level-shifters are needed - simplifying layout and improving accuracy in cordless tool battery monitoring using the INA241A4IDR.

What is the typical input bias current of the INA241A4IDR, and why does it matter for shunt selection?

The INA241A4IDR draws 35µA (typical) input bias current per input pin - and critically, this value remains constant across its full −20V to 120V common-mode range. Unlike competitive amplifiers whose bias current scales with V_CM, this stability ensures predictable gain error with low-value shunts (e.g., 0.5mΩ–5mΩ) in high-current motor phases, preserving accuracy in designs using the INA241A4IDR.

Does the INA241A4IDR require special PCB layout practices to maintain its 166dB DC-CMRR?

Yes. To preserve the INA241A4IDR's 166dB DC-CMRR, symmetric routing of IN+ and IN− traces is mandatory - including matched length, width, and proximity to ground planes. REF1/REF2 traces must also be routed as a tightly coupled pair. Asymmetric parasitics degrade CMRR; TI recommends guard rings around sense-node traces and separation from noisy digital lines - practices validated in motor drive reference designs using the INA241A4IDR.