Diodes AH287 User Manual
Ah287, Typical application circuit, Features

AH287
HIGH VOLTAGE HALL-EFFECT SMART FAN MOTOR
CONTROLLER
AH287 Rev. 10
1 of 11
APRIL 2010
DS31042
©
Diodes Incorporated
•
On Chip Hall Sensor
• Rotor-Locked
Shutdown
• Automatically
Restart
•
Built-in Zener Protection for Output Driver
•
Operating Voltage: 3.8V~28V
• Output
Current:
I
O(AVE)
= 400mA
•
Lead Free Packages: SIP-4L and SOT89-5L (Note 1)
•
SIP-4L and SOT89-5L: Available in “Green” Molding
Compound (No Br, Sb)
•
Lead Free Finish/ RoHS Compliant (Note 2)
AH287 is a monolithic fan motor controller with Hall sensor’s
capability. It contains two complementary open-drain drivers for
motor’s coil driving, automatic lock shutdown and restart function
relatively.
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.
Typical Application Circuit
DOB
DO
24V
L2
L1
GND
287
1
2
3
4
D2
48V
48V
C1
D1
D3
Note: The optional Capacitor C1 and Diode D3 are for power stabilization. C1 is recommended to be E-Cap., luF/25V;
D3 is recommended to be Zener Diode, V
Z
=27V. Which C1and D3 value need to be fine tuned to optimize
design for different coils and power suppliers.
24V Brush-Less DC Fan
Features
General Description