Diodes Incorporated AH3574-SA-7

Overview

AH3574-SA-7 from Diodes Incorporated is a high-voltage, high-sensitivity Hall effect omnipolar switch IC in SOT23 package, designed for non-contact position and proximity sensing. It operates from 3.0V to 28V, features ±40G typical operate point (BOP), ±25G typical release point (BRP), and delivers open-drain output with 30–55mA current limiting-used in smart home appliance door detection and industrial flow metering.

For engineers reviewing the AH3574-SA-7 datasheet, AH3574-SA-7 pinout, AH3574-SA-7 application, or AH3574-SA-7 equivalent, this device supports robust magnetic sensing across -40°C to +125°C, integrates chopper stabilization for <15G hysteresis stability, includes reverse battery protection, and requires no external biasing for South/North pole actuation.

Technical Context

The AH3574 employs dynamic offset cancellation via chopper-stabilized architecture operating at 800kHz, enabling minimal switch-point drift over temperature. Its internal bandgap regulator supplies temperature-compensated voltage to analog blocks, ensuring stable BOP/BRP thresholds across the full -40°C to +125°C range.

It integrates reverse-blocking diode and Zener clamps on both VDD and OUTPUT pins, supporting transient supply voltages up to ±32V. The single open-drain output switches low when |B| exceeds BOP and remains latched until |B| falls below BRP-enabling reliable bounce-free switching without external debouncing.

Key Specifications

Pinout & Package

Package: SOT23 - surface-mount, 3-pin, lead-free, RoHS-compliant package with 2.4mm × 1.3mm footprint and 1.1mm height; optimized for automated assembly and thermal dissipation up to 230mW at 25°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AL3505-30D and TLE4913-2K, the AH3574-SA-7 uniquely combines omnipolar detection, reverse-battery tolerance, and 3.0V start-up in SOT23-making it optimal for cost-sensitive, space-constrained industrial and appliance designs requiring zero-polarity assembly and wide-input flexibility.

Availability

AH3574-SA-7 is available at Aetrix Electronics and suitable for smart home appliance door detection, industrial flow metering, factory automation position feedback, and building occupancy sensing requiring stable component supply across extended temperature and voltage ranges.

Supply support for AH3574-SA-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 manufacturer of discrete semiconductors and ICs, specializing in high-reliability signal integrity, power management, and sensing solutions for industrial, automotive, and consumer markets.

The AH3574 belongs to Diodes' Hall-effect sensor product line, engineered specifically for robust, maintenance-free position and proximity sensing in unregulated 12V/24V systems exposed to temperature extremes and electrical transients.

FAQ

What is the minimum supply voltage required for reliable operation of AH3574-SA-7?

The AH3574-SA-7 requires a minimum supply voltage of 3.0V to guarantee valid output sampling and stable chopper operation. Below 3.0V, the internal bandgap regulator cannot maintain proper biasing, resulting in undefined output states and potential latch-up. Startup is guaranteed within 10µs once VDD reaches 3.0V.

Does AH3574-SA-7 require an external pull-up resistor on the OUTPUT pin?

Yes - the OUTPUT pin is an open-drain configuration and requires an external pull-up resistor to VDD or another logic rail. Typical values range from 1kΩ to 10kΩ depending on rise time and noise immunity requirements. The datasheet recommends RL = 1kΩ for 0.2µs rise time with 20pF load capacitance.

Can AH3574-SA-7 operate with magnets placed on the backside of the SOT23 package?

No - the AH3574-SA-7 is sensitive to magnetic flux perpendicular to the top surface (marked side) of the SOT23 package. For SOT23, the Hall element is located beneath the marking surface; placing the magnet on the backside results in significantly reduced sensitivity or no detection due to shielding and flux path misalignment.

Is AH3574-SA-7 qualified for automotive applications?

The AH3574-SA-7 is not AEC-Q200 qualified and lacks automotive-specific screening (e.g., HTOL, temperature cycling). While its -40°C to +125°C operating range and 28V tolerance meet some automotive subsystem requirements, Diodes Incorporated positions it for industrial and consumer applications-not safety-critical or under-hood automotive use.