AH9479/80/81
Document number: DS41222 Rev. 3 - 4
1 of 13
www.diodes.com
July 2018
© Diodes Incorporated
AH9479/80/81
OBSOL ETE – P A RT D ISCO N T INU ED
1
2
3
4
VCC
OUT1
OUT2
GND
SINGLE PHASE LOW NOISE SMART MOTOR DRIVER
Description
The AH9479/80/81 is a single chip solution for driving single coil
brushless DC motors. It combines a motor driver with a high
sensitivity Hall sensor, which simplifies the PCB design and makes
the fabrication of small-size motors possible.
The AH9480 has an open-drain tachometer output FG that follows the
Hall sensor latching output. The AH9481 has an open-drain rotation
detection output RD that is active low when the motor is spinning and
goes high when blocked.
When there is no motion about 0.4 second, the IC will automatically
detect the locked rotor conditions, and enter protection mode, shutting
off the motor driver for 4 seconds. Then, the IC will turn on the motor
driver for 0.4 second to detect whether there is rotation condition, if
fails, the IC will shut off motor driver for four seconds again. This
sequence will be repeated until rotation condition is detected, and the
IC enters normal operation. This feature can effectively prevent the IC
from overheating and damage due to long-time locked rotor condition.
“Soft-switch” is used to reduce the vibration and acoustic noise.
Thermal-shutdown protection ensures that the motor driver operates
under specified temperature ranges.
The AH9479 is packaged in TO-94, and the AH9480/81 is packaged
in MSOP-8.
Features
Full Bridge Driver
High Sensitivity Integrated Hall Sensor
Soft-Switching for Low Noise
Low Supply Voltage: 2.5V
Locked Rotor Protection and Auto-Restart
Thermal Protection
Output Over-Current Protection
Short Circuit Protection
Tachometer Output Signal (AH9480)
Alarm Output Signal (AH9481)
1
2
3
4
8
7
6
5
NC
FG/RD
GND
OUT1
GND
OUT2
VCC
NC
PART OBSOLETE - USE AH5772/5773
AH9479/80/81
Document number: DS41222 Rev. 3 - 4
2 of 13
www.diodes.com
July 2018
© Diodes Incorporated
AH9479/80/81
OBSOL ETE – P A RT D IS C ONT IN UED
Typical Applications Circuit
1
2
3
4
8
7
6
5
NC
FG/RD
GND
OUT1
NC
VCC
GND
OUT2
5V
C1
D2
FG/RD
AH9480/81
R1
D1
VCC
COIL
Note 1: C1 should be at least larger than 2.2μF, R1=0 to 10Ω
Pin Descriptions
Pin Number
Pin Name
Function
TO-94
MSOP-8
_
2
FG/RD
Frequency generator (rotation detection) open drain output
1
7
VCC
Power supply pin
2
4
OUT1
Output pin 1
3
6
OUT2
Output pin 2
4
3, 5
GND
Ground pin
_
1, 8
NC
No connection
AH9479
VCC
OUT2
GND
OUT1
1
2 3
4
COIL
D1
R1
C1
D2
PART OBSOLETE - USE AH5772/5773