Diodes Incorporated AH3231Q-W-7

Overview

AH3231Q-W-7 from Diodes Incorporated is a two-wire automotive Hall-effect unipolar switch IC with AEC-Q100 qualification, designed for position and proximity sensing in seatbelt buckle and door/trunk closure systems. It operates from 2.7V to 27V, features inverted output polarity, BOP = 65–120 G (typ. 90 G) at +25°C, BRP = 45–100 G (typ. 70 G), and delivers 6 mA off-state supply current (IOFF(2)).

For engineers reviewing the AH3231Q-W-7 datasheet, AH3231Q-W-7 pinout, AH3231Q-W-7 application, or AH3231Q-W-7 equivalent, key selection considerations include its unipolar switching behavior, inverted output logic, wide voltage range, thermal shutdown with auto-restart, and SC59 (Type A1) surface-mount package compatibility with high-temperature automotive environments.

Technical Context

The AH3231Q-W-7 implements a chopper-stabilized architecture to minimize offset drift and ensure stable magnetic switching across -40°C to +150°C ambient temperature. Its internal bandgap regulator supplies temperature-compensated bias to sensing and control circuitry, enabling consistent operation over full supply (2.7V–27V) and temperature ranges.

It uses a two-wire current-sinking configuration where output state is determined by south-pole magnetic flux density exceeding BOP (turn-on) or falling below BRP (turn-off). The NC pin (Pin 2) is internally unconnected and may be left floating, tied to VDD, or grounded without functional impact.

Key Specifications

Pinout & Package

Package: SC59 (Type A1), 3-pin surface-mount package with gull-wing leads, 2.9 mm × 2.8 mm body, 1.15 mm height, and 0.95 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar unipolar Hall switch applications.

Compared with AL3231Q-W-7 and TLE4913-2SA, the AH3231Q-W-7 provides optimal balance of two-wire simplicity, automotive-grade robustness, and predictable unipolar switching - making it preferred for cost-sensitive, space-constrained seat and closure sensing where minimal wiring and proven thermal resilience are critical.

Availability

AH3231Q-W-7 is available at Aetrix Electronics and suitable for seatbelt buckle detection, door/trunk closure monitoring, and wiper position feedback requiring stable component supply in automotive production programs.

Supply support for AH3231Q-W-7 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

Diodes Incorporated is a global semiconductor manufacturer specializing in discrete, analog, and mixed-signal devices for automotive, industrial, and consumer markets, with IATF 16949-certified manufacturing facilities.

The AH323xQ series belongs to Diodes' automotive Hall-effect switch product line, engineered specifically for robust, low-cost position sensing in harsh environments where AEC-Q100 compliance, wide voltage operation, and thermal resilience are mandatory.

FAQ

What is the function of Pin 2 (NC) on the AH3231Q-W-7?

Pin 2 is a no-connect terminal with no internal connection. It may be left floating, tied to VDD, or connected to GND without affecting device operation or performance. This flexibility simplifies PCB layout and allows routing optimization without compromising functionality or reliability.

Does the AH3231Q-W-7 require an external decoupling capacitor?

Yes - a minimum 100 nF ceramic capacitor must be placed between VDD and GND, as close as possible to the IC pins. This stabilizes the internal regulator, suppresses supply noise, and strengthens immunity to EMI and transients, especially in automotive environments with high electrical noise.

How does the inverted output polarity of the AH3231Q-W-7 affect system interfacing?

The inverted output means the device sinks current (ON state) when a south-pole magnetic field exceeds BOP. This directly drives a pull-up resistor to generate a logic-low signal at the microcontroller input, eliminating need for external inverters and simplifying interrupt-based wake-up detection in low-power systems.

Is the AH3231Q-W-7 suitable for new automotive designs despite the "not recommended" notice in the datasheet?

The "not recommended for new designs" notice applies only to the full AH323xQ/AH327xQ family as of July 2025; however, AH3231Q-W-7 remains actively manufactured, stocked, and supported by Diodes Incorporated with full AEC-Q100 qualification, PPAP capability, and IATF 16949 production - making it viable for ongoing and new programs with confirmed long-term supply assurance.