Texas Instruments INA4181A2IPWR

Overview

INA4181A2IPWR from Texas Instruments is a quad-channel, bidirectional current-sense amplifier with 50 V/V fixed gain, –0.2 V to +26 V input common-mode range, ±500 µV max offset at 12 V VCM, and 210 kHz small-signal bandwidth. It enables precision high- and low-side current monitoring in motor control, battery management, and solar inverter power stages.

For engineers reviewing the INA4181A2IPWR datasheet, INA4181A2IPWR pinout, INA4181A2IPWR application, or INA4181A2IPWR equivalent, key selection criteria include guaranteed 50 V/V gain accuracy (±1% max), rail-to-rail output swing (within 30 mV of VS and 5 mV of GND), 2 V/µs slew rate, and operation across –40°C to +125°C with 900 µA max quiescent current.

Technical Context

The INA4181A2IPWR integrates four independent current-sense amplifiers in a single TSSOP-20 package, each featuring matched internal gain resistors for 50 V/V operation. Its proprietary topology supports common-mode voltages up to 26 V - independent of its 2.7–5.5 V supply - enabling direct sensing on high-voltage bus rails without level-shifting circuitry.

Each channel uses a differential input stage with REF pin biasing to support bidirectional current detection: positive IN+–IN– yields OUT > VREF; negative differential yields OUT < VREF. Output voltage follows VOUT = GAIN × (IN+ – IN–) + VREF, with rail-to-rail capability and 2 V/µs slew rate ensuring fast transient response in fault-detection and closed-loop motor control loops.

Key Specifications

Pinout & Package

The INA4181A2IPWR is housed in a 20-pin TSSOP (PW) package measuring 6.50 mm × 6.40 mm, with exposed thermal pad recommended for grounding to improve thermal performance (R_θJA = 97.0°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA4181A1IPWR and INA4181A3IPWR, the INA4181A2IPWR delivers the optimal balance of sensitivity (50× gain), speed (210 kHz), and offset performance for mid-range current monitoring in motor drives and battery systems - avoiding the bandwidth sacrifice of A3 or the reduced resolution of A1.

Availability

INA4181A2IPWR is available at Aetrix Electronics and suitable for motor control, battery monitoring, and solar inverter applications requiring stable component supply, extended temperature qualification, and quad-channel integration.

Supply support for INA4181A2IPWR 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, embedded processing, and connectivity technologies for industrial, automotive, and communications markets.

The INA4181A2IPWR belongs to TI's INAx181 family of cost-optimized, bidirectional current-sense amplifiers designed specifically for high-accuracy, high-voltage current monitoring in space- and power-constrained systems.

FAQ

What is the maximum common-mode voltage supported by the INA4181A2IPWR?

The INA4181A2IPWR 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 level-shifting circuitry. The specification is guaranteed across the full operating temperature range (–40°C to +125°C) and applies to all four channels of the INA4181A2IPWR.

How does the REF pin function in the INA4181A2IPWR?

The REF pin in the INA4181A2IPWR sets the output voltage baseline for bidirectional current sensing: VOUT = 50 × (IN+ – IN–) + VREF. Applying VREF = VS/2 centers the output at mid-supply, enabling detection of both positive and negative current flow with a single-ended ADC. Each of the four channels has its own dedicated REF pin (REF1–REF4), allowing independent biasing per channel in the INA4181A2IPWR.

What is the typical quiescent current consumption of the INA4181A2IPWR?

The INA4181A2IPWR draws a maximum of 900 µA quiescent current across all four channels at 25°C, with a typical value of ~690 µA. At full temperature range (–40°C to +125°C), the maximum remains 900 µA. This low power draw makes the INA4181A2IPWR suitable for always-on current monitoring in battery-backed systems and energy-sensitive industrial controllers.

Can the INA4181A2IPWR be used for both high-side and low-side current sensing?

Yes, the INA4181A2IPWR supports both high-side and low-side current sensing configurations. For high-side use, connect IN+ to the bus voltage side and IN– to the load side of the shunt; for low-side, connect IN+ to the load side and IN– to ground. Its –0.2 V to +26 V common-mode range and rail-to-rail output ensure accuracy in either configuration - a core capability confirmed for the INA4181A2IPWR in TI's SBOS793H datasheet.

What package type and pin count does the INA4181A2IPWR use?

The INA4181A2IPWR is packaged in a 20-pin TSSOP (PW) package measuring 6.50 mm × 6.40 mm, with an exposed thermal pad. Pin assignments include four independent sets of IN+, IN–, OUT, and REF (pins 1–4, 6–9, 12–15, 17–20), plus shared VS (pin 5), GND (pin 16), and two NC pins (10, 11). This package is specified in TI's official packaging documentation for the INA4181A2IPWR.