ah291 Diodes, Inc., ah291 Datasheet - Page 3

• Manufacturer Part Number: ah291
• Description: Low Voltage Hall-effect Smart Fan Motor Controller
• Manufacturer: Diodes, Inc.

Block Diagram
Typical Application Circuit
AH291 Rev. 2
Regulator
1.8V/5.75V
V
1
dd
Notes: R1, R2: typical
The R, C value need to be fine tuned
based on coils design.
Plate
Hall
C1, C2, C3: typical 2.2 F
( SIP-4L )
Amp.
V
dd
D1
C3
56
1.8V/5.75V Brush-Less DC Fan
LOW VOLTAGE HALL-EFFECT SMART FAN MOTOR
O
www.diodes.com
μ
Automatic Recovery
DO
1
D2
Lock Shutdown
3 of 10
4
Control Logic
2
291
GND
and
3
4
GND
DOB
R1
C1
L2
2
3
CONTROLLER
DECEMBER 2006
DOB
DO
©
Diodes Incorporated
AH291
C2
R2
L1