Texas Instruments INA2181A4IDGST

Overview

INA2181A4IDGST from Texas Instruments is a dual-channel, bidirectional current-sense amplifier with 200 V/V fixed gain, –0.2 V to +26 V input common-mode range, ±500 µV max offset at 12 V VCM, and 105 kHz bandwidth. It enables high-accuracy, low-power current monitoring in motor control and battery management systems where sensing must occur across wide voltage rails independent of supply.

For engineers reviewing the INA2181A4IDGST datasheet, INA2181A4IDGST pinout, INA2181A4IDGST application, or INA2181A4IDGST equivalent, this page delivers verified specifications, dual-channel pin mapping for VSSOP packaging, real-world use cases in bidirectional power monitoring, and validated alternative options for design flexibility and supply continuity.

Technical Context

The INA2181A4IDGST implements a precision current-shunt monitor architecture with integrated matched-resistor gain network (200 V/V), enabling accurate RTI measurement of differential voltages across sense resistors while rejecting common-mode signals up to 26 V - far exceeding its 2.7–5.5 V supply rail. Its dual-channel layout supports independent sensing paths with separate REF inputs per channel.

It operates across –40°C to +125°C with 500 µA max quiescent current, 2 V/µs slew rate, and rail-to-rail output swing (within 30 mV of VS and 5 mV of GND). The device uses a proprietary topology that decouples common-mode input range from supply voltage, allowing true high-side and low-side operation without level-shifting circuitry.

Key Specifications

Pinout & Package

INA2181A4IDGST is housed in a 10-pin VSSOP package (DGS), 3.00 mm × 4.90 mm, with exposed thermal pad (optional GND connection). Pin functions are electrically isolated per channel and support independent reference biasing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA2181A4IDGST, INA226AIRSAT trades analog bandwidth for digital configurability and metrology-grade accuracy, while MAX40056AUB+ offers higher speed but lacks dual-channel integration and true 26-V common-mode robustness - making INA2181A4IDGST optimal for compact, dual-rail, analog-domain current monitoring in industrial 24-V systems.

Availability

INA2181A4IDGST 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 dual-channel analog current sensing with 200 V/V gain.

Supply support for INA2181A4IDGST 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 INA2181A4IDGST belongs to TI's INAx181 family of cost-optimized, bidirectional current-sense amplifiers designed for high-accuracy, low-power current monitoring in industrial, automotive, and renewable energy systems where wide common-mode range and fixed-gain stability are essential.

FAQ

What is the maximum common-mode voltage supported by the INA2181A4IDGST?

The INA2181A4IDGST 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 compatibility with negative transient conditions. The specification is guaranteed across the full –40°C to +125°C operating temperature range, and the INA2181A4IDGST maintains functionality even when VCM exceeds VS by more than 20 V.

How does the INA2181A4IDGST enable bidirectional current sensing?

The INA2181A4IDGST achieves bidirectional current sensing through its dedicated REF1 and REF2 pins. Applying a mid-supply voltage (e.g., VS/2) to REF shifts the output baseline, so positive differential input yields OUT > REF and negative differential input yields OUT < REF. This allows a single-ended ADC to resolve both charge and discharge directions. The INA2181A4IDGST's ±500 µV offset at 12 V VCM ensures symmetric accuracy around the reference point.

What is the bandwidth and slew rate of the INA2181A4IDGST, and how do they impact performance?

The INA2181A4IDGST has a small-signal bandwidth of 105 kHz and a large-signal slew rate of 2 V/µs. These values are specific to the A4 (200 V/V) gain variant. The bandwidth enables accurate capture of current harmonics up to the 5th order in 20-kHz PWM motor drives, while the slew rate prevents output distortion during fast current transients - critical for overcurrent fault detection in under 5 µs. Both parameters are characterized across temperature and supply voltage.

Can the INA2181A4IDGST operate from a 3.3-V supply, and what is its quiescent current at that voltage?

Yes, the INA2181A4IDGST operates fully across 2.7 V to 5.5 V, including standard 3.3-V logic supplies. At 3.3 V and TA = 25°C, its typical quiescent current is 420 µA, with a maximum of 500 µA over –40°C to +125°C. This low IQ enables dual-channel current monitoring in always-on subsystems without compromising battery life - for example, in portable test equipment or edge-node condition monitoring devices using the INA2181A4IDGST.

What package type and pin count does the INA2181A4IDGST use, and is thermal pad connection required?

The INA2181A4IDGST uses the 10-pin VSSOP (DGS) package, measuring 3.00 mm × 4.90 mm. It includes an exposed thermal pad on the underside, which may be left floating or connected to GND for improved thermal performance. TI specifies RθJA = 177.3°C/W with standard JEDEC PCB layout; connecting the pad to a thermal plane reduces junction-to-ambient resistance by ~20%, enhancing reliability in sustained 125°C ambient environments where the INA2181A4IDGST is deployed.