AH288
HIGH VOLTAGE HALL-EFFECT SMART FAN MOTOR
CONTROLLER
AH288 Rev. 12 1 of 9 APRIL 2010
DS31040 www.diodes.com © Diodes Incorporated
• On chip Hall sensor
• Rotor-locked shutdown
• Automatically restart
• Frequency generator (FG) output
• Built-in Zener protection for output driver
• Operating voltage: 3.8V~28V
• Output current: I
O(AVE)
= 400mA
• Lead Free Package: SOT89-5L (Note 1)
• SOT89-5L: Available in “Green” Molding Compound
(No Br, Sb)
• Lead Free Finish/RoHS Compliant (Note 2)
AH288 is a monolithic fan motor controller with Hall sensor’s
capability. It contains two complementary open-drain transistors
as motor coil drivers, automatic lock current shutdown, and
recovery protections. Additional, frequency generator (FG) output
is for speed detection 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
288
1
3
2
Vdd
(24V)
Coil2
Coil1
R
pu
FG
D2
D1
* Rpu : typical 10 Kohm
C1
5 4
48V
48V
GND
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 DC Brush-less Fan with FG output function
Features
General Description
