Texas Instruments INA2181A3IDSQT

Overview

INA2181A3IDSQT 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 INA2181A3IDSQT datasheet, INA2181A3IDSQT pinout, INA2181A3IDSQT application, or INA2181A3IDSQT equivalent, key selection criteria include its 100 V/V gain accuracy (±1% max), 2 V/µs slew rate, rail-to-rail output swing (within 30 mV of VS and 5 mV of GND), and dual-channel isolation for independent current sensing paths in compact power systems.

Technical Context

The INA2181A3IDSQT implements a matched-resistor gain network for stable 100 V/V amplification, minimizing gain error drift across temperature (≤20 ppm/°C). Its proprietary topology supports common-mode voltages beyond the 2.7–5.5 V supply, enabling direct sensing on 26 V buses without level-shifting circuitry.

Each channel operates independently with dedicated IN+, IN–, OUT, and REF pins. The device uses internal precision resistors-no external gain-setting components-ensuring consistent performance across production lots and eliminating layout sensitivity to parasitic capacitance or trace mismatch.

Key Specifications

Pinout & Package

INA2181A3IDSQT is housed in a 10-pin WSON package (DSQ), 2.00 mm × 2.00 mm, thermally enhanced with exposed thermal pad (optional GND connection).

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA2181A2IDSQT and INA2290AIDR, the INA2181A3IDSQT delivers optimal resolution for mid-range currents (0.1–5 A) with analog immediacy and dual-channel independence - critical for real-time protection and closed-loop control where latency and channel crosstalk must be minimized.

Availability

INA2181A3IDSQT is available at Aetrix Electronics and suitable for motor control, battery monitoring, and solar inverter applications requiring stable component supply, extended temperature operation, and dual-channel current sensing integrity.

Supply support for INA2181A3IDSQT 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 INA2181 series belongs to TI's current-sense amplifier product line, engineered specifically for cost-optimized, high-accuracy bidirectional current monitoring in industrial, automotive, and renewable energy systems where wide common-mode range and rail-to-rail output are essential.

FAQ

What is the maximum common-mode voltage supported by the INA2181A3IDSQT?

The INA2181A3IDSQT 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 and robust low-side operation near ground, making the INA2181A3IDSQT suitable for applications like motor drives and battery management where bus voltages exceed the IC's supply rails.

How does the REF pin function in the INA2181A3IDSQT?

The REF pin in the INA2181A3IDSQT sets the output voltage baseline: V_OUT = 100 × (V_IN+ – V_IN–) + V_REF. Applying 0 V enables unidirectional current sensing; applying V_S/2 enables bidirectional operation with symmetric output swing. Each channel has its own REF pin (REF1, REF2), allowing independent configuration - a key capability of the INA2181A3IDSQT in dual-path monitoring systems.

What is the small-signal bandwidth of the INA2181A3IDSQT and how does it relate to gain option?

The INA2181A3IDSQT has a small-signal bandwidth of 150 kHz, specified for the A3 (100 V/V) gain variant. Bandwidth scales inversely with gain: A1 (20 V/V) = 350 kHz, A2 (50 V/V) = 210 kHz, A3 (100 V/V) = 150 kHz, A4 (200 V/V) = 105 kHz. This trade-off ensures stability and predictable step response - the INA2181A3IDSQT's 150 kHz bandwidth supports accurate current sampling in 20 kHz PWM motor control loops.

Can the INA2181A3IDSQT be used for both high-side and low-side current sensing?

Yes, the INA2181A3IDSQT supports both configurations. For high-side sensing, connect IN+ to the bus and IN– to the load side of the shunt; for low-side, connect IN+ to the load and IN– to ground. Its –0.2 V to +26 V common-mode range and rail-to-rail output ensure accuracy in either topology - a defining feature of the INA2181A3IDSQT that eliminates need for separate high- and low-side ICs.

What is the quiescent current consumption of the INA2181A3IDSQT and why does it matter?

The INA2181A3IDSQT draws a maximum of 500 µA from its 2.7–5.5 V supply, covering both channels across –40°C to +125°C. This low quiescent current enables continuous current monitoring in always-on subsystems - such as battery fuel gauging or standby power supervision - without compromising system energy budget, a critical advantage of the INA2181A3IDSQT in portable and remote industrial equipment.