Texas Instruments INA199A3RSWR

Overview

INA199A3RSWR from Texas Instruments is a bidirectional, zero-drift current-shunt monitor optimized for high-accuracy, low-power current sensing in both high-side and low-side configurations. It features 200 V/V fixed gain, ±150 μV maximum offset voltage, –0.3 V to 26 V common-mode input range, 100 μA max quiescent current, and operates from 2.7 V to 26 V supply. It enables 10-mV full-scale shunt measurements in notebook battery management and Qi wireless charging transmitters.

For engineers reviewing the INA199A3RSWR datasheet, INA199A3RSWR pinout, INA199A3RSWR application, or INA199A3RSWR equivalent, this page delivers verified electrical specs, package mapping to UQFN-10, validated pin functions, thermal performance data, and real-world implementation guidance for precision current monitoring in space-constrained, thermally sensitive systems.

Technical Context

The INA199A3RSWR uses a zero-drift chopper-stabilized architecture to achieve ±150 μV offset and 0.5 μV/°C drift over –40°C to +125°C, enabling accurate sub-10-mV shunt voltage detection. Its differential input stage supports bidirectional sensing with 120 dB CMRR at DC and maintains stability across its 14 kHz bandwidth (G = 200) with 1 nF capacitive load tolerance.

It integrates matched internal resistors (R3 = R4 = 5 kΩ) for 200 V/V gain, accepts REF input from 0 V to V+, and draws only 65–100 μA supply current - making it suitable for always-on power rail monitoring in battery-powered devices without compromising measurement fidelity.

Key Specifications

Pinout & Package

INA199A3RSWR is packaged in a 10-pin UQFN (RSW) with 1.80 mm × 1.40 mm body size and 0.5-mm pitch. The package supports fine-pitch PCB assembly and offers low thermal resistance (R_θJB = 18.7°C/W) for high-density power management layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA240A3D and MAX40056ATA+T, INA199A3RSWR uniquely balances 26-V common-mode capability, UQFN-10 thermal efficiency, and 100-μA quiescent current - making it optimal for space-constrained, wide-input industrial and battery-powered systems requiring robust bidirectional sensing without external level shifters.

Availability

INA199A3RSWR is available at Aetrix Electronics and suitable for notebook battery management, Qi wireless charging transmitters, and industrial 24-V power supply monitoring requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for INA199A3RSWR 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 for industrial, automotive, and personal electronics markets.

The INA199 product line was designed specifically for high-accuracy, low-power current sensing in space-constrained applications - emphasizing zero-drift performance, wide common-mode operation, and flexible gain options for battery, power supply, and motor control systems.

FAQ

What is the maximum common-mode voltage supported by the INA199A3RSWR?

The INA199A3RSWR supports a common-mode input voltage range of –0.3 V to 26 V across its full operating temperature range of –40°C to +125°C. This specification applies specifically to the INA199A version, as confirmed in Section 6.5 of the SBOS469H datasheet. The device maintains functionality even when the input common-mode voltage exceeds the V+ supply rail, enabling direct high-side sensing on 24-V systems without external level-shifting circuitry. The INA199A3RSWR achieves this via its proprietary high-voltage input stage design.

Does the INA199A3RSWR require external resistors to set gain?

No, the INA199A3RSWR does not require external resistors to set gain. It features a factory-trimmed, fixed 200 V/V gain implemented with internal matched thin-film resistors (R3 = R4 = 5 kΩ), as specified in Table 4 and Section 7.4.1 of the SBOS469H datasheet. This eliminates gain-setting errors from external component tolerances and layout parasitics. The device is part of the INA199x3 variant family, and its gain is permanently configured - no external feedback network is needed or recommended for standard operation.

Can the INA199A3RSWR be used for bidirectional current sensing?

Yes, the INA199A3RSWR supports true bidirectional current sensing. Its output voltage is referenced to the externally applied REF pin voltage, allowing the output to swing above and below REF depending on current direction through the shunt resistor. When REF is set to mid-supply (e.g., V+/2), the output centers at that voltage for zero current and deviates positively or negatively with forward or reverse current flow. This behavior is explicitly documented in the Functional Block Diagram (Section 7.2) and Typical Applications (Section 8.2) of the SBOS469H datasheet.

What is the thermal resistance of the INA199A3RSWR in its UQFN-10 package?

The INA199A3RSWR in the RSW (UQFN-10) package has a junction-to-board thermal resistance (R_θJB) of 18.7°C/W, as specified in Section 6.4 of the SBOS469H datasheet. This low value reflects efficient heat transfer from the die to the PCB copper plane through the exposed thermal pad. For reliable operation at maximum ambient temperatures, designers should ensure the thermal pad is soldered to a minimum 100 mm² copper area with ≥4 thermal vias to inner ground planes. The R_θJA of 107.3°C/W assumes standard JEDEC 2S2P test conditions.

How does the zero-drift architecture of the INA199A3RSWR improve measurement accuracy?

The zero-drift architecture of the INA199A3RSWR reduces input offset voltage to ±150 μV maximum and limits offset drift to 0.5 μV/°C over –40°C to +125°C. This enables accurate current measurement using shunt resistors with full-scale voltage drops as low as 10 mV - reducing power loss by 90% compared to conventional 100-mV shunts. The chopper-stabilized design actively corrects offset in real time, eliminating the need for periodic system-level calibration. These performance values are measured and guaranteed per Section 6.5 of the SBOS469H datasheet.