Texas Instruments INA303A1QPWRQ1

Overview

INA303A1QPWRQ1 from Texas Instruments is an AEC-Q100 Grade 1 (–40°C to +125°C) bidirectional current-sense amplifier with integrated dual-window comparator, 20 V/V gain, ±125 mV input range, and 550-kHz bandwidth. It operates from 2.7 V to 5.5 V supply, draws ≤950 µA quiescent current, and delivers 30 µV max offset voltage for high-precision shunt-based motor or DC/DC converter current monitoring.

For engineers reviewing the INA303A1QPWRQ1 datasheet, INA303A1QPWRQ1 pinout, INA303A1QPWRQ1 application, or INA303A1QPWRQ1 equivalent, key selection criteria include its window-comparator architecture (vs. overlimit-only INA302-Q1), 1 µs ALERT1 response, user-adjustable ALERT2 delay (2 µs–10 s), and –0.1 V to +36 V common-mode input range enabling high-side sensing in automotive body control modules.

Technical Context

The INA303A1QPWRQ1 implements a zero-drift chopper-stabilized amplifier core with 114 dB typical CMRR and 4 V/µs slew rate, enabling accurate bidirectional current measurement across wide common-mode voltages. Its dual-comparator block features independent limit inputs (LIMIT1/LIMIT2), open-drain ALERT1/ALERT2 outputs with latch/transparent mode control via LATCH1/LATCH2, and programmable ALERT2 delay via external capacitor on DELAY pin.

Unlike the overlimit-only INA302-Q1, the INA303-Q1 family uses LIMIT1 and LIMIT2 to define upper and lower thresholds - forming a true window comparator - allowing detection of both overcurrent and undercurrent faults. Thresholds are set by external resistors sourcing 80 µA nominal current, and hysteresis is fixed at 100 mV to prevent chatter near trip points.

Key Specifications

Pinout & Package

INA303A1QPWRQ1 is housed in a 14-pin TSSOP package (4.40 mm × 5.00 mm body size) with exposed thermal pad. Pin functions are validated per TI SBOS977A datasheet Figure 5-1 and Table 5-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA303A2QPWRQ1 and INA240A1QPWRQ1, the INA303A1QPWRQ1 provides optimal balance of gain, speed, and integrated window-comparator functionality for cost-sensitive automotive subsystems requiring both overcurrent and undercurrent detection in a single chip.

Availability

INA303A1QPWRQ1 is available at Aetrix Electronics and suitable for motor control and protection, DC/DC converters, and body control module applications requiring stable component supply across automotive production lifecycles.

Supply support for INA303A1QPWRQ1 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 automotive, industrial, and personal electronics markets.

The INA30x-Q1 product line is designed specifically for automotive current-sensing applications requiring AEC-Q100 qualification, high common-mode tolerance, and integrated fault detection - targeting body electronics, powertrain subsystems, and ADAS power management.

FAQ

What is the maximum common-mode voltage the INA303A1QPWRQ1 can withstand?

The INA303A1QPWRQ1 supports continuous operation with common-mode input voltages from –0.1 V to +36 V and can survive transient stresses up to +40 V without damage. This enables direct high-side current sensing on 12 V and 24 V automotive battery rails while powered from a separate 3.3 V or 5 V supply - a key capability for space-constrained body control modules where level-shifting circuitry would add cost and complexity.

How does the window-comparator function differ between INA303A1QPWRQ1 and INA302A1QPWRQ1?

The INA303A1QPWRQ1 implements a true window comparator using LIMIT1 (upper threshold) and LIMIT2 (lower threshold) to detect both overcurrent and undercurrent events simultaneously. In contrast, the INA302A1QPWRQ1 uses two independent overlimit comparators - both triggered only when current exceeds a set threshold. This makes the INA303A1QPWRQ1 uniquely suited for applications like pump monitoring, where detecting loss-of-flow (undercurrent) is as critical as detecting locked-rotor (overcurrent).

What is the purpose of the DELAY pin on the INA303A1QPWRQ1?

The DELAY pin on the INA303A1QPWRQ1 controls the response time of the ALERT2 output via an external capacitor. With C_DELAY, ALERT2 delay is programmable from 2 µs to 10 s; omitting the capacitor yields minimum delay (~2 µs), while connecting a 100 kΩ resistor from DELAY to VS achieves fastest possible response. This flexibility prevents false alarms during inrush currents while maintaining fast fault detection for sustained overloads - a critical feature for automotive DC/DC converter protection.

Can the INA303A1QPWRQ1 measure bidirectional current, and how is polarity indicated?

Yes, the INA303A1QPWRQ1 supports bidirectional current sensing by applying a reference voltage (e.g., 2.5 V) to the REF pin. When current flows in one direction, the OUT voltage rises above V_REF; when reversed, OUT falls below V_REF. For example, with V_REF = 2.5 V and 20 V/V gain, ±125 mV differential input produces an output swing of 2.25 V to 2.75 V - enabling full-range ADC capture of both directions using a single-ended input.

What are the latch and transparent modes for ALERT1 and ALERT2 on the INA303A1QPWRQ1?

LATCH1 and LATCH2 pins configure ALERT1 and ALERT2 to operate in either transparent mode (output follows input state in real time) or latched mode (output remains low after fault detection until manually reset). In latched mode, the alert persists to ensure fault visibility even if the overcurrent condition clears briefly - essential for diagnostic logging in automotive ECUs. The latch is cleared by toggling the respective LATCHx pin or cycling power.