AH3772
HIGH-VOLTAGE, HIGH-SENSITIVITY HALL EFFECT LATCH
Description Pin Assignments
The AH3772 is a high-voltage, high-sensitivity Hall Effect latch IC
designed for commutation of brushless DC motors, flow meters,
(Top View)
linear encoders, and position sensors in industrial and consumer
home appliances and personal care applications. To support a wide
3 OUTPUT
range of demanding applications, the design is optimized to operate
GND 2
over the supply range of 3.0V to 28V. With chopper-stabilized
1 V
DD
architecture and an internal bandgap regulator to provide
temperature compensated supply for internal circuits, the AH3772
provides a reliable solution over the whole operating range. For SC59 and SOT23
robustness and protection, the device has a reverse-blocking diode
with a zener clamp on the supply. The output has an overcurrent limit
and a zener clamp.
(Top View)
The single open-drain output can be switched on with South pole of
3. OUTPUT
sufficient strength and switched off with North pole of sufficient
2. GND
strength. When the magnetic-flux density (B) perpendicular to the
package is larger than the operate point (B ), the output is switched
OP
1. V
DD
on (pulled low). The output is held latched until magnetic-flux density
SIP-3
reverses and becomes lower than the release point (B ).
RP
Applications
Features
Brushless DC Motor Commutation
Bipolar Latch (South Pole: On, North Pole: Off)
Revolution Per Minute (RPM) Measurement
3.0V to 28V Operating Voltage Range
Flow Meters
High Sensitivity: B and B of +25G and -25G Typical
OP RP
Angular and Linear Encoder and Position Sensors
Single, Open-Drain Output with Overcurrent Limit
Contactless Commutation, Speed Measurement, and Angular
Chopper-Stabilized Design Provides
Position Sensing/Indexing in Consumer Home Appliances, Office
- Superior Temperature Stability
Equipment, and Industrial Applications
- Minimal Switch-Point Drift
- Enhanced Immunity to Stress
Good RF Noise Immunity
Reverse-Blocking Diode and Zener Clamp on Supply
-40C to +125C Operating Temperature
ESD (HBM): 6kV
Industry Standard SC59, SOT23 and SIP-3 Packages
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. Green Device (Note 3)
Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant.
2. See Low-Pass Filter
Sample and
Hold
Dynamic Offset
Cancellation
AH3772
Typical Applications Circuit (Note 4)
3.0V to 28V
V
DD
R
L
OUTPUT
AH3772
C
IN
GND
Note: 4. C is for power stabilization and to strengthen the noise immunity, the recommended capacitance is 10nF ~ 100nF. R is the pull-up resistor.
IN L
Pin Descriptions
Package: SOT23 and SIP-3
Pin Number Pin Name Function
1 V Power Supply Input
DD
2 GND Ground
3 OUTPUT Output Pin
Functional Block Diagram
V
DD
Power
switch
To All Subcircuits
OUTPUT
Amp
Amp Control
Current
Limit
GND
2 of 14
AH3772 April 2018
Diodes Incorporated
www.diodes.com
Document number: DS38106 Rev. 2 - 2
PRELIMINARY - CONFIDENTIAL