Texas Instruments INA302A3IPW

Overview

INA302A3IPW from Texas Instruments is a 36-V, bidirectional current-sense amplifier with dual integrated comparators configured for overcurrent protection. It delivers 100 V/V gain, ±30 µV max offset voltage, and <1 µs alert response on COMP1 - deployed in motor control, server power rails, and telecom DC-DC modules to detect fault currents before MOSFET or PCB damage occurs.

For engineers reviewing the INA302A3IPW datasheet, INA302A3IPW pinout, INA302A3IPW application, or INA302A3IPW equivalent, this page provides verified functional context, TSSOP-14 pin mapping, real-world use cases, and two validated alternative parts with documented technical and application-level differences.

Technical Context

The INA302A3IPW integrates a zero-drift, high-common-mode (–0.1 V to +36 V) current-sense amplifier with two independent comparators: COMP1 triggers within 1 µs on overlimit events, while COMP2 supports adjustable delay (2 µs to 10 s) via external CDELAY. Its 100 V/V gain enables precise sensing of low differential voltages (±25 mV full-scale) across shunt resistors in high-voltage systems.

Both comparators feature open-drain ALERT outputs with independent latch/transparent mode control via LATCH1/LATCH2 pins, and threshold setting via internal 80 µA current sources at LIMIT1/LIMIT2 pins - allowing resistor-based threshold programming without external references or DACs.

Key Specifications

Pinout & Package

Packaged in a 14-pin TSSOP (4.4 mm × 5.0 mm), the INA302A3IPW supports surface-mount assembly and thermal dissipation up to 110.2°C/W junction-to-ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar overcurrent protection applications.

Compared with INA303A3IPW, the INA302A3IPW provides dedicated dual overcurrent alerts without undercurrent detection - simplifying threshold design in motor or power-supply shutdown systems. Against MAX40056ASA+, the INA302A3IPW integrates delay, latch, and dual comparators, reducing component count and improving fault-response determinism.

Availability

INA302A3IPW is available at Aetrix Electronics and suitable for motor control, server power-rail monitoring, and telecom DC-DC module protection requiring stable component supply and long-term industrial lifecycle support.

Supply support for INA302A3IPW 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 INA30x product line was designed specifically for high-accuracy, high-common-mode current sensing in industrial, computing, and communications infrastructure - integrating amplification, comparison, and fault timing in a single compact package.

FAQ

What is the maximum common-mode voltage the INA302A3IPW can handle?

The INA302A3IPW supports a common-mode input voltage range of –0.1 V to +36 V. This allows direct high-side or low-side current sensing on 12 V, 24 V, and 36 V power rails without level-shifting circuitry. The specification is guaranteed across the full operating temperature range (–40°C to +125°C) and is independent of the 2.7–5.5 V supply voltage applied to the VS pin. This capability is essential for protecting power stages in motor drives and telecom equipment.

How does the ALERT2 delay function work on the INA302A3IPW?

The ALERT2 delay on the INA302A3IPW is set by an external capacitor (CDELAY) connected between the DELAY pin and GND. An internal 5 µA current source charges CDELAY until it reaches a 1.22 V threshold, triggering the comparator. Delay time = CDELAY × 1.22 V / 5 µA - yielding 2 µs to 10 s range. For example, a 100 pF capacitor gives ~24.4 ns delay, while a 10 µF capacitor yields ~2.44 s. The DELAY pin must remain unconnected for minimum delay operation.

Can the INA302A3IPW measure bidirectional current, and how is that configured?

Yes, the INA302A3IPW supports bidirectional current sensing via the REF pin. Applying a mid-supply voltage (e.g., 2.5 V when VS = 5 V) to REF centers the OUT voltage at that level. A positive IN+–IN– differential produces an OUT above REF; a negative differential produces OUT below REF. This enables detection of both sourcing and sinking currents - critical for H-bridge motor control or regenerative braking circuits - using a single device and one shunt resistor.

What is the purpose of the LATCH1 and LATCH2 pins on the INA302A3IPW?

LATCH1 and LATCH2 are digital inputs that configure the behavior of ALERT1 and ALERT2 outputs, respectively. When pulled high, each comparator output latches low upon overlimit detection and remains asserted until manually cleared (e.g., by toggling the latch pin or cycling power). When pulled low, the output operates in transparent mode - following the real-time comparator state. This enables flexible fault-handling strategies: latched mode for persistent fault indication, transparent mode for continuous monitoring in closed-loop systems.

What shunt resistor value is recommended for use with the INA302A3IPW at 100 V/V gain?

For the INA302A3IPW's 100 V/V gain and ±25 mV input range, a 2 mΩ shunt is optimal for 10 A full-scale measurement (10 A × 2 mΩ = 20 mV). This yields 2 V output swing (20 mV × 100), well within the 0.05 V to VS–0.1 V output swing limits. Lower values (e.g., 1 mΩ) support 20 A measurement with <0.5 W power loss; higher values increase loss and noise susceptibility. Layout must minimize parasitic inductance and ensure Kelvin connections to IN+ and IN–.