Diodes AH293 User Manual
Ah293

AH293
LOW VOLTAGE HALL-EFFECT SMART FAN MOTOR
CONTROLLER
AH293
Document number: DS31048 Rev. 6 - 2
1 of 8
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
• Output Current: I
O(AVE)
= 400 mA
• 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
Typical Application Circuit
(Note 1)
293
1
5
4
3
2
V
dd
(1.8V/5.75V)
Coil2
Coil1
R
pu
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