Texas Instruments INA2181A1IDSQR

Overview

INA2181A1IDSQR from Texas Instruments is a dual-channel, bidirectional current-sense amplifier with 20 V/V fixed gain, –0.2 V to +26 V input common-mode range, 350 kHz bandwidth, ±150 µV max offset at 0 V VCM, and 2 V/µs slew rate. It enables precision low- and high-side current monitoring in motor control, battery management, and power supply systems where bus voltages exceed supply rails.

For engineers reviewing the INA2181A1IDSQR datasheet, INA2181A1IDSQR pinout, INA2181A1IDSQR application, or INA2181A1IDSQR equivalent, key selection criteria include bidirectional sensing capability, rail-to-rail output swing (within 30 mV of VS and 5 mV of GND), guaranteed ±1% gain error over –40°C to +125°C, and compatibility with 2.7–5.5 V single-supply operation.

Technical Context

The INA2181A1IDSQR implements a matched-resistor gain network for 20 V/V amplification, eliminating external gain-setting components and minimizing temperature-induced gain drift. Its proprietary topology supports accurate current measurement across –0.2 V to +26 V common-mode voltage independent of its 2.7–5.5 V supply, enabling direct connection to high-voltage buses without level-shifting circuitry.

Each channel features independent IN+, IN–, OUT, and REF pins, supporting simultaneous bidirectional sensing per channel via reference voltage biasing. The device draws ≤500 µA quiescent current and operates across –40°C to +125°C, with CMRR ≥84 dB and PSRR ≤±40 µV/V over full temperature range.

Key Specifications

Pinout & Package

INA2181A1IDSQR is housed in a 10-pin WSON package (DSQ), 2.0 mm × 2.0 mm, with exposed thermal pad (optional GND connection). Pin count and layout match TI's DSQ footprint for mechanical and thermal compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA2181A1IDSQR, INA219AIDR trades analog dual-channel flexibility for integrated digital conversion, while MAX40056ATA+T offers higher bandwidth but sacrifices 6 V of common-mode headroom-critical for robust 24-V system operation.

Availability

INA2181A1IDSQR is available at Aetrix Electronics and suitable for motor control, battery monitoring, and solar inverter applications requiring stable component supply, extended temperature operation (–40°C to +125°C), and precise bidirectional current sensing.

Supply support for INA2181A1IDSQR 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 INA2181A1IDSQR belongs to TI's INAx181 family of cost-optimized, fixed-gain current-sense amplifiers designed specifically for high-accuracy, low-drift bidirectional current measurement in industrial, automotive, and renewable energy systems.

FAQ

What is the maximum common-mode voltage supported by the INA2181A1IDSQR?

The INA2181A1IDSQR 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 24-V industrial buses without external attenuation or level-shifting circuitry, and is fully specified across –40°C to +125°C. The INA2181A1IDSQR maintains accuracy even when VCM exceeds VS by up to 20.5 V.

Does the INA2181A1IDSQR support bidirectional current sensing on both channels simultaneously?

Yes, the INA2181A1IDSQR supports true bidirectional current sensing on both channels independently. Each channel has dedicated REF1 and REF2 pins to set the zero-current output level; applying VREF = VS/2 yields symmetric ±VOUT swing for positive and negative current flow. This capability is inherent to the INA2181A1IDSQR architecture and requires no external switches or configuration.

What is the guaranteed gain error specification for the INA2181A1IDSQR over temperature?

The INA2181A1IDSQR guarantees ±1% maximum gain error over the full operating temperature range of –40°C to +125°C. This is explicitly specified in Section 6.5 of the SBOS793H datasheet under "EG Gain error" conditions. Unlike some alternatives that specify gain error only at 25°C, the INA2181A1IDSQR's ±1% limit applies across the entire industrial temperature range, simplifying system calibration.

Can the INA2181A1IDSQR be used in low-side current sensing configurations?

Yes, the INA2181A1IDSQR is fully qualified for low-side current sensing. Its ±150 µV maximum offset voltage at VCM = 0 V enables accurate measurement of small differential voltages across low-value shunts (e.g., 1–10 mΩ). The device's rail-to-rail output swing (within 5 mV of GND) preserves dynamic range when interfacing with low-voltage ADCs, and its 350 kHz bandwidth captures fast transient currents typical in switched-mode loads.

What package type and thermal characteristics does the INA2181A1IDSQR have?

INA2181A1IDSQR uses the DSQ (10-pin WSON) package: 2.0 mm × 2.0 mm body with exposed thermal pad. Its junction-to-ambient thermal resistance (RθJA) is 74.5°C/W, and junction-to-board (RθJB) is 39.8°C/W - significantly lower than VSSOP alternatives. This enables reliable operation at full spec in compact, thermally constrained PCB layouts without forced airflow, especially critical in sealed industrial enclosures.