Texas Instruments INA181A1IDBVR

Overview

INA181A1IDBVR from Texas Instruments is a single-channel, bidirectional current-sense amplifier optimized for high-accuracy, low-power monitoring in both high-side and low-side configurations. It features 20 V/V fixed gain, ±150 µV max offset at 0 V common-mode, 350 kHz bandwidth, and operates from 2.7 V to 5.5 V supply across –40°C to +125°C - enabling precise motor phase current sensing in industrial drives.

For engineers reviewing the INA181A1IDBVR datasheet, INA181A1IDBVR pinout, INA181A1IDBVR application, or INA181A1IDBVR equivalent, key selection criteria include its –0.2 V to +26 V input common-mode range independent of supply, 2 V/µs slew rate for fast fault detection, ±1% max gain error over temperature, and SOT-23-6 package compatibility with space-constrained PCB layouts.

Technical Context

The INA181A1IDBVR employs a precision current-sense topology with integrated matched resistor network for 20 V/V gain, eliminating external gain-setting components and minimizing temperature-induced gain drift. Its input stage supports true differential sensing across –0.2 V to +26 V common-mode voltage, decoupled from the 2.7–5.5 V supply rail - enabling direct connection to 12 V or 24 V bus rails without level-shifting.

Operation relies on REF pin biasing to enable bidirectional output swing: positive load current yields VOUT > VREF; negative current yields VOUT < VREF. The device achieves rail-to-rail output capability with ≤30 mV headroom to VS and ≤5 mV to GND under 10 kΩ load, supporting direct interfacing with 12-bit ADCs or microcontroller analog inputs.

Key Specifications

Pinout & Package

INA181A1IDBVR is housed in a 6-pin SOT-23 (DBV) package measuring 2.90 mm × 2.80 mm, optimized for automated assembly and thermal performance in high-density power boards.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA240A1IDR and MAX40056ATA+T, the INA181A1IDBVR offers the best balance of ultra-low power (260 µA), compact SOT-23-6 footprint, and sufficient accuracy (±150 µV, ±1%) for cost-sensitive industrial and battery-powered designs operating up to 26 V.

Availability

INA181A1IDBVR is available at Aetrix Electronics and suitable for motor control, battery monitoring, and solar inverter applications requiring stable component supply, long-term manufacturability, and guaranteed traceability.

Supply support for INA181A1IDBVR 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 INA181 family targets cost-optimized, high-reliability current sensing in industrial, automotive, and renewable energy systems - delivering integrated gain, wide common-mode range, and low power in minimal footprint.

FAQ

What is the maximum common-mode voltage the INA181A1IDBVR can handle?

The INA181A1IDBVR 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 connection to 24 V bus rails in motor drives or industrial PLCs without external attenuation or level-shifting circuitry. Absolute maximum rating is 26 V per datasheet Section 6.1, and operation beyond this may cause permanent damage.

Can the INA181A1IDBVR measure bidirectional current, and how is it configured?

Yes, the INA181A1IDBVR supports bidirectional current sensing by applying a reference voltage (VREF) to its REF pin - typically mid-supply (e.g., 2.5 V for 5 V VS). Positive differential input yields VOUT > VREF; negative differential yields VOUT < VREF. This configuration enables accurate monitoring of charge/discharge cycles in battery systems or forward/reverse motor operation without hardware polarity reversal.

What is the gain setting of the INA181A1IDBVR, and is it adjustable?

The INA181A1IDBVR has a fixed gain of 20 V/V, determined by an internal matched resistor network. This eliminates external gain-setting components, improves temperature stability (gain drift ≤1.5 ppm/°C), and reduces layout sensitivity. Gain is not user-adjustable; alternative variants include INA181A2 (50 V/V), INA181A3 (100 V/V), and INA181A4 (200 V/V).

Does the INA181A1IDBVR require external compensation or filtering?

No external compensation is required - the INA181A1IDBVR is internally compensated for unity-gain stability. However, a 0.1 µF ceramic bypass capacitor is mandatory between VS and GND, placed as close as possible to the pins. For noisy environments, a small RC filter (e.g., 10 Ω + 1 nF) on the IN+ and IN– lines may improve EMI immunity without degrading 350 kHz bandwidth.

What package type is used for the INA181A1IDBVR, and what are its thermal characteristics?

The INA181A1IDBVR uses the 6-pin SOT-23 (DBV) package, measuring 2.90 mm × 2.80 mm. Its junction-to-ambient thermal resistance (RθJA) is 198.7°C/W, and junction-to-board (RθJB) is 52.3°C/W. For continuous operation at full ambient temperature (125°C), power dissipation must remain below ~125 mW - well within its 260 µA IQ limit at 5 V (1.3 mW typical).