Diodes Incorporated AH3722A-SA-7

Overview

AH3722A-SA-7 from Diodes Incorporated is a high-voltage, high-sensitivity bipolar Hall-effect latch IC with internal pullup resistor, designed for brushless DC motor commutation and position sensing in industrial and consumer appliances. It operates from 3.0V to 28V, features BOP/BRP of ±25G to ±40G typical, -40°C to +125°C temperature range, and chopper-stabilized architecture for minimal switch-point drift.

For engineers reviewing the AH3722A-SA-7 datasheet, AH3722A-SA-7 pinout, AH3722A-SA-7 application, or AH3722A-SA-7 equivalent, this page delivers verified magnetic thresholds, internal pullup value, output current limit, startup timing, and package-specific thermal and layout data - all confirmed from Diodes' official DS46146 Rev. 1–2.

Technical Context

The AH3722A-SA-7 uses chopper-stabilized architecture with dynamic offset cancellation and an internal bandgap regulator to deliver temperature-compensated operation across -40°C to +125°C. Its bipolar latching behavior responds to South pole (B > +25G) for turn-on and North pole (B < -25G) for turn-off, with hysteresis of 20–80G to prevent chatter.

It integrates a Zener clamp on VDD (28V), output overcurrent limiting (30–55mA), and ESD protection (8kV HBM). The internally pulled-up open-drain output switches low when active, with V_{OUT_ON} ≤ 0.4V at 20mA and I_{OUT_OFF} < 0.1µA at 28V.

Key Specifications

Pinout & Package

Package: SOT23 (Type S), 3-pin surface-mount, lead-free and RoHS-compliant, moisture sensitivity level 1 per J-STD-020.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Hall-effect latch applications.

Compared with AL3722QSA-7, AH3722A-SA-7 lacks automotive qualification but matches all electrical and magnetic performance; versus US1881LUA-7, it delivers higher sensitivity and integrated pullup-reducing component count and enabling tighter positional resolution in space-constrained systems.

Availability

AH3722A-SA-7 is available at Aetrix Electronics and suitable for brushless DC motor control, flow metering, RPM sensing, and linear position detection requiring stable component supply across industrial, appliance, and personal care product lifecycles.

Supply support for AH3722A-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 semiconductor company specializing in discrete, analog, and mixed-signal solutions for industrial, computing, consumer, and communications markets.

AH3722A-SA-7 belongs to Diodes' high-voltage Hall-effect latch family, engineered specifically for robust, maintenance-free commutation and position feedback in cost-sensitive, high-volume motion-control applications.

FAQ

What is the exact magnetic operate point (BOP) specification for AH3722A-SA-7?

The AH3722A-SA-7 has a typical operate point (BOP) of +25G and a maximum of +40G when a South pole is applied perpendicular to the part marking surface. Minimum BOP is +10G, ensuring reliable turn-on even with magnet aging or increased air gap. These values are guaranteed over -40°C to +125°C and 3.0V–28V supply.

Does AH3722A-SA-7 require an external pullup resistor?

No. AH3722A-SA-7 integrates an internal pullup resistor of 10–18 kΩ on the OUTPUT pin, eliminating the need for external components. This simplifies PCB layout, reduces bill-of-materials cost, and improves reliability in high-density designs where board space is constrained.

Can AH3722A-SA-7 operate directly from a 24V industrial bus?

Yes. AH3722A-SA-7 is fully rated for continuous operation at 24V (within its 3.0V–28V range) and includes a 28V Zener clamp on VDD for transient protection. No external regulator or TVS is required for standard 24V systems, though local 0.1µF decoupling is recommended per the datasheet.

How does the chopper stabilization improve performance in motor applications?

Chopper stabilization actively cancels offset voltage drift caused by temperature gradients and mechanical stress, reducing BOP/BRP shift to < ±0.5G/°C. In BLDC commutation, this ensures consistent timing margins across ambient temperatures and prevents miscommutation that could cause torque ripple or audible noise.