Data Sheet
TWO PHASE HALL EFFECT LATCH WITH LOCKED PROTECTION
AH287
General Description
The AH287 is an integrated Hall sensor with output
drivers for brushless DC motor application. This IC
consists of two complementary outputs for motor’s
coil driving and has automatic lock protection and
auto- restart function relatively. To avoid coil burning,
rotor lock shutdown protection circuit shut down the
output driver if the rotor blocked and then the
automatic recovery circuit will try to restart the motor.
This function repeats while rotor is blocked. Until the
blocking is removed, the motor recovers running
normally. In addition, the auto-restart time is flexible
by adjusting the capacitance (C
CT
).
Placing the device in a variable magnetic field, if the
magnetic flux density is larger than threshold B
OP
, the
DO is turned to sink and DOB is turned to drive. This
output state is held until a magnetic flux density
reversal falls below B
RP
, causing DO to be turned to
drive and DOB turned to sink.
This IC is available in TO-94 package.
Features
•
•
•
•
•
•
•
•
•
•
On-chip Hall Sensor
Operating Voltage: 3.5V to 18V
Maximum Output Current: 350mA (ave)
Rotor-locked Protection
Automatic Restart
Adjustable Auto-restart Time
Internal Band-gap Regulator for Temperature
Compensation
Operating Temperature: -20˚C to 85˚C
Low Profile TO-94 Package
ESD Rating: 300V (Machine Model)
Application
•
Dual-coil Brushless DC Fan
TO-94
Figure 1. Package Type of AH287
Oct. 2009
Rev. 1. 3
1
BCD Semiconductor Manufacturing Limited
BCDSEMI [ BCD SEMICONDUCTOR MANUFACTURING LIMITED ]
