Diodes Incorporated AH286-YL-13

Overview

AH286 from Diodes Incorporated is a Hall-effect smart fan motor controller IC designed for two-coil brushless DC (BLDC) cooling fans. 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 rotor-lock protection timing (tRLP-ON = 0.5s typ., tRLP-OFF = 3s typ.), magnetic sensitivity (Bop = 10–60 Gauss), output saturation voltage (VOUT(SAT) = 375–900mV at 300–500mA), RD flag logic (low during rotation, high on lock), and thermal derating profile up to +100°C ambient.

Technical Context

The AH286 implements a latch-type Hall sensing architecture with built-in amplifier and dynamic offset cancellation to reject mechanical stress-induced drift. Its control logic autonomously detects rotor stall via magnetic field absence, triggers output shutdown, asserts the RD flag high, and initiates automatic re-start after lock removal.

Each open-drain output driver features internal Zener clamping (Vz = 35–60V), RDS(ON) ≤1.67Ω at 300mA, and supports bidirectional coil commutation in two-phase BLDC configurations. The device regulates only power delivery-not speed or PWM-making it a fixed-function motor sequencer rather than a programmable controller.

Key Specifications

Pinout & Package

The AH286 is housed in a thermally enhanced SOT89-5 surface-mount package with exposed thermal pad (pin 4 connected to GND internally). Pin 1 is DOB (complementary output), pin 2 is DO (main output), pin 3 is GND, pin 4 is RD (rotor-lock detect), and pin 5 is Vdd.

Key Features

Applications

Availability

AH286 is available at Aetrix Electronics and suitable for server rack cooling fans, industrial PLC fan modules, medical diagnostic equipment fans, and network switch heat management 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, specializing in power management, signal integrity, and precision analog solutions for industrial, computing, and consumer markets.

The AH286 belongs to Diodes' Hall-effect motor controller product line, engineered specifically for cost-sensitive, high-reliability BLDC fan applications where integration, stall protection, and thermal robustness are critical design requirements.

FAQ

Is the AH286 pin-compatible with any active Diodes replacement parts?

No. Diodes Incorporated explicitly states "NO ALTERNATE PART" and marks AH286 as obsolete with no drop-in or functional replacement. The AH286-YL-13 variant uses SOT89-5 packaging and green material; no successor part replicates its exact Hall sensor offset correction, RD flag behavior, or dual-output timing architecture.

What is the function of the RD pin during normal operation?

The RD pin is an open-drain output that remains low during normal rotor rotation and transitions high only when rotor lock is detected. It requires an external pull-up resistor (typically 10kΩ to Vdd) to generate a logic-high signal for microcontroller GPIO monitoring or fault logging circuits.

Can the AH286 drive a three-coil BLDC motor?

No. The AH286 is designed exclusively for two-coil (two-phase) BLDC motors. Its functional block diagram, truth table, and pin assignments confirm only two complementary outputs (DO and DOB); it lacks the third phase drive capability or commutation logic required for three-phase motors.

Does the AH286 require external components for basic operation?

Yes. Minimum external components include pull-up resistors on DO, DOB, and RD pins; decoupling capacitors (C1/C2/C3 ≥2.2μF per datasheet note 4); and optionally a Zener diode between Vdd and GND for overvoltage protection. No external clock, PWM, or configuration resistors are needed for core operation.