Diodes AH477A User Manual
Data Sheet
SINGLE PHASE HALL EFFECT LATCH AH477A
General Description
The AH477A is an integrated Hall sensor with Hbridged output driver designed for brushless DC motor
applications. The device includes an on-chip Hall sensor for magnetic sensing, an amplifier that amplifies
the Hall voltage, a comparator to provide switching
hysteresis for noise rejection, a bi-directional drivers
for sinking and driving large current load. It also
includes an internal bandgap regulator to provide temperature compensated bias for internal circuits and
allows a wide operating supply voltage range.
Placing the device in a variable magnetic field, if the
magnetic flux density is larger than threshold B
DO is turned to sink and DOB is turned to drive. This
output state is held until the magnetic flux density
reverses and falls below B
turned to drive and DOB turned to sink.
The AH477A is available in TO-94 (SIP-4L) package.
then causes DO to be
RP,
OP
, the
Features
· On-Chip Hall Sensor
· Operating Voltage: 3.5V to 18V
· H-Bridge Output Drivers for Single Coil
· Internal Bandgap Regulator for Temperature
Compensation
· Low Output Switching Current Noise
o
· Operating Temperature: -20
· Low Profile TO-94 (SIP-4L) Package
· ESD Rating: 6000V (Human Body Model)
· Suitable for PWM Power Supply Control Speed
C to 85oC
Applications
· Single-coil Brushless DC Motor
· Single-coil Brushless DC Fan
TO-94
Figure 1. Package Type of AH477A
Oct. 2009 Rev. 1. 2 BCD Semiconductor Manufacturing Limited
1
Data Sheet
SINGLE PHASE HALL EFFECT LATCH AH477A
Pin Configuration
Z4 Package
(TO-94)
Pin Description
Pin Number Pin Name Function
1
2 DO Output 1
3 DOB Output 2
4 GND Ground
4
3
2
1
Figure 2. Pin Configuration of AH477A (Front View)
V
CC
Supply voltage
GND
DOB
DO
V
CC
Oct. 2009 Rev. 1. 2 BCD Semiconductor Manufacturing Limited
2
Data Sheet
SINGLE PHASE HALL EFFECT LATCH AH477A
Functional Block Diagram
V
CC
1
V
CC
Regulator
2
DO
Hall
Sensor
Ordering Information
Circuit Type
Package
Z4: TO-94 (SIP-4L)
Amplifier
Figure 3. Functional Block Diagram of AH477A
AH477A
Schmitt
Trigger
-
Pre-
Driver
V
CC
G1: Green
Magnetic Characteristics
A: 5 to 70 Gauss
B: 100 Gauss
3
DOB
4
GND
Package Temperature Range Part Number Marking ID Packing Type
TO-94
BCD Semiconductor's Pb-free products, as designated with "G1" suffix in the part number, are RoHS compliant and green.
-20 to 85
o
C
AH477AZ4-AG1 477AZ4-G1 Bulk
AH477AZ4-BG1 477AZ4-G1 Bulk
Oct. 2009 Rev. 1. 2 BCD Semiconductor Manufacturing Limited
3
Loading...