Diodes Incorporated AH286-PL-B

Overview

AH286 from Diodes Incorporated is a Hall-effect smart fan motor controller IC designed for two-coil brushless DC (BLDC) cooling fans and low-power motors. It integrates a Hall sensor, dynamic offset correction, dual complementary open-drain drivers with internal Zener protection, rotor-lock detection (RD), and automatic restart-operating from 3.8V to 20V with average output current up to 500mA in SOT89-5 package.

For engineers reviewing the AH286 datasheet, AH286 pinout, AH286 application, or AH286 equivalent, key selection considerations include its integrated Hall sensing, Rotor Lock Protection timing (0.4–0.6s ON / 2.4–3.6s OFF), RD flag logic (low during rotation, high on lock), V_OUT(SAT) ≤ 900mV at 500mA, and thermal derating curve down to 0mW at +150°C junction temperature.

Technical Context

The AH286 implements a latch-type Hall sensor with magnetic operate point (B_OP) of 10–60 Gauss and release point (B_RP) of –60 to –10 Gauss, enabling reliable commutation for two-phase BLDC motors. Its control logic autonomously detects rotor stall via back-EMF monitoring and triggers output shutdown within 0.5s typical, followed by 3s typical hold-off before auto-restart.

Each open-drain output driver features internal Zener clamping (35–60V breakdown), R_DS(ON) ≤ 1.67Ω at 300mA, and thermal shutdown coordination with θ_JA = 156°C/W. The RD output provides TTL-compatible status signaling with V_OL ≤ 0.5V at 10mA sink current.

Key Specifications

Pinout & Package

Package: SOT89-5, surface-mount, thermally enhanced 5-pin plastic package with exposed thermal pad (pin 4 is GND-connected tab).

Key Features

Applications

Availability

AH286 is available at Aetrix Electronics and suitable for two-coil BLDC cooling fans, low-voltage server chassis fans, and industrial low-power BLDC pumps requiring stable component supply despite end-of-life status.

Supply support for AH286 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 analog ICs, headquartered in Plano, Texas, with design and manufacturing operations across Asia and the Americas.

The AH286 belongs to Diodes' Smart Motor Control product line, engineered specifically for cost-sensitive, space-constrained BLDC fan and pump applications requiring integrated Hall sensing and autonomous stall protection.

FAQ

Is the AH286 still in active production?

No-the AH286 is officially marked obsolete by Diodes Incorporated with no alternate part offered. Aetrix Electronics maintains limited legacy stock and supports last-time buys with full traceability and documentation per original DS31030 Rev. 13 datasheet.

Can the AH286 drive a three-phase BLDC motor?

No-it is designed exclusively for two-coil (single-phase commutated, two-terminal) BLDC fans and motors. Its functional block diagram shows only two complementary outputs (DO/DOB) and lacks the third phase driver, timing logic, or Hall decoding required for three-phase operation.

What is the purpose of the RD pin's active-high lock signal?

The RD pin outputs high when rotor lock is detected and low during normal rotation, providing immediate, polarity-matched status to microcontrollers or monitoring circuits. Its open-drain structure allows flexible pull-up voltage selection (e.g., 3.3V or 5V) independent of Vdd.

Does the AH286 require external flyback diodes across motor coils?

No-each output includes an internal Zener diode (35–60V breakdown) that clamps inductive kickback from the motor windings. External diodes are unnecessary unless system-level surge immunity beyond 60V is required.