AH293

LOW VOLTAGE HALL-EFFECT SMART FAN MOTOR

CONTROLLER

AH293

Document number: DS31048 Rev. 6 - 2

1 of 8

www.diodes.com

June 2010

© Diodes Incorporated

Description

AH293 is a monolithic fan motor controller with Hall sensor’s

capability. It contains two complementary open-collector

transistors for Motor’s coil driving, automatic lock current

shutdown,

and

recovery

protections.

Also,

rotor-state

detection (RD) output is for speed detection.

Rotor-lock shutdown detection circuit turns off the output

driver when the rotor is blocked to avoid coil overheat. Then,

the automatic recovery circuit will restart the motor. These

protected actions are repeated and periodic during the

blocked period. Until the blocking is removed, the motor

recovers and runs normally.

The AH293 is available in SOT89-5L package.

Features

•

On Chip Hall Sensor

•

Rotor-Locked Shutdown

•

Automatically Restart

•

Rotor-State Detection (RD) Output

•

Built-in Zener Protection for Output Driver

•

Operating Voltage: 1.8V~5.75 V

•

•

Packaged in SOT89-5L

•

Green Molding Compound

Pin Assignments

1

2

3

74

5

DOB

DO

GND

RD

Vdd

SOT89-5L

293

(Top View)

Applications

•

Two-coil BLDC cooling fans

•

Low to medium voltage, low power BLDC motors

293

1

5

4

3

2

(1.8V/5.75V)

Coil2

Coil1

RD

(alarm)

GND

D2

D1

R1

R2

C1

C2

Notes:

1. R1, R2: typical 56 Ohm

C1, C2, C3: typical 2.2µF

The R, C value need to be fine tuned based

on coils design.

C3

1.8V/5.75V DC Brush-Less Fan with RD Output Function