Texas Instruments INA2181A3IDSQR

Overview

INA2181A3IDSQR from Texas Instruments is a dual-channel, bidirectional current-sense amplifier with 100 V/V fixed gain, –0.2 V to +26 V input common-mode range, ±500 µV max offset at 12 V VCM, and 150 kHz small-signal bandwidth. It enables precision high- and low-side current monitoring in motor control and battery management systems where bus voltages exceed supply rails.

For engineers reviewing the INA2181A3IDSQR datasheet, INA2181A3IDSQR pinout, INA2181A3IDSQR application, or INA2181A3IDSQR equivalent, key selection criteria include its 100 V/V gain accuracy (±1% max), rail-to-rail output swing (within 30 mV of VS and 5 mV of GND), bidirectional sensing capability via REF pin biasing, and operation across –40°C to +125°C.

Technical Context

The INA2181A3IDSQR integrates matched thin-film gain resistors for 100 V/V amplification, minimizing gain error drift (1.5 ppm/°C) and enabling accurate current measurement independent of supply voltage. Its proprietary topology supports common-mode voltages up to 26 V while powered from only 2.7 V to 5.5 V.

Each channel features independent IN+, IN–, OUT, and REF pins, allowing separate bidirectional sensing paths. The device achieves 150 kHz bandwidth and 2 V/µs slew rate-optimized for fast transient detection in motor phase current or fault-current monitoring without external compensation.

Key Specifications

Pinout & Package

INA2181A3IDSQR is housed in a 10-pin WSON package (DSQ), 2.00 mm × 2.00 mm, with exposed thermal pad (optional GND connection). Pinout supports dual independent current-sense channels with dedicated reference inputs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA229AIDGST and MAX40056ATA+T, the INA2181A3IDSQR uniquely balances dual-channel analog output, 26-V common-mode support, and 100-V/V precision gain in a compact WSON package-making it optimal for cost-sensitive, space-constrained industrial motor and battery systems requiring analog-domain integration.

Availability

INA2181A3IDSQR is available at Aetrix Electronics and suitable for motor control, battery management, and solar inverter applications requiring stable component supply, extended temperature operation, and high common-mode voltage resilience.

Supply support for INA2181A3IDSQR 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 power management ICs.

The INA2181A3IDSQR belongs to TI's INAx181 family of current-sense amplifiers, designed specifically for cost-optimized, high-accuracy bidirectional current monitoring in motor drives, battery systems, and power supplies operating across wide common-mode voltage ranges.

FAQ

What is the maximum common-mode voltage supported by the INA2181A3IDSQR?

The INA2181A3IDSQR 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 level-shifting circuitry. The specification is validated across the full –40°C to +125°C operating temperature range and is not dependent on VS level.

How does the INA2181A3IDSQR achieve bidirectional current sensing?

The INA2181A3IDSQR achieves bidirectional sensing by using the REF1 and REF2 pins to set a DC bias point for each channel's output. When the differential input (IN+ – IN–) is positive, OUT exceeds VREF; when negative, OUT falls below VREF. With VREF = VS/2, the output swings symmetrically around mid-supply-enabling single-supply systems to resolve both charge and discharge currents.

What is the typical bandwidth and slew rate of the INA2181A3IDSQR?

The INA2181A3IDSQR has a small-signal bandwidth of 150 kHz and a large-signal slew rate of 2 V/µs. These values are specified for the A3 gain variant (100 V/V) with 10-pF load capacitance. The bandwidth enables accurate capture of motor current harmonics up to ~15 kHz, while the slew rate supports fast fault detection in overcurrent protection circuits.

Can the INA2181A3IDSQR operate from a 3.3-V supply?

Yes, the INA2181A3IDSQR operates from 2.7 V to 5.5 V, making 3.3-V systems fully compatible. At 3.3 V, its rail-to-rail output swings within 30 mV of VS and 5 mV of GND, delivering ≥3.25 V of usable dynamic range. Quiescent current remains ≤500 µA, ensuring minimal impact on low-power system budgets.

What package type and thermal characteristics does the INA2181A3IDSQR use?

The INA2181A3IDSQR uses the DSQ (10-pin WSON) package, 2.00 mm × 2.00 mm, with an 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. The thermal pad may be left floating or connected to GND to improve heat dissipation in high-temperature ambient designs.