AH3777
HIGH-VOLTGAE LOW-SENSITIVITY HALL EFFECT LATCH
Description
The AH3777 is a high voltage, low sensitivity Hall effect latch IC
designed for commutation of brushless DC motors, flow meters,
linear encoders and position sensors in industrial and consumer
home appliance and personal care applications. To support a wide
range of demanding applications, the design is optimized to operate
over the supply range of 3.0V to 28V. With chopper-stabilized
architecture and an internal bandgap regulator to provide
temperature compensated supply for internal circuits, the AH3777
provides a reliable solution over the whole operating range. For
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.
The single, open-drain output can be switched on with South pole of
sufficient strength and switched off with North pole of sufficient
strength. When the magnetic flux density (B) perpendicular to the
package is larger than the operate point (BOP) the output is switched
on (pulled low). The output is held latched until magnetic flux density
reverses and becomes lower than the release point (BRP).
Pin Assignments
(Top View)
GND 2
3 OUTPUT
1 VDD
SOT23
(Top View)
SIP-3
3. OUTPUT
2. GND
1. VDD
Features
• Bipolar Latch Operation (South Pole: On, North Pole: off)
• 3.0V to 28V Operating Voltage Range
• Low Sensitivity: BOP and BRP of +140G and -140G Typical
• Single, Open-Drain Output with Overcurrent Limit
• Chopper Stabilized Design Provides
- Superior Temperature Stability
- Minimal Switch Point Drift
- Enhanced Immunity to Stress
• Good RF Noise Immunity
• Reverse Blocking Diode and Zener Clamp on Supply
• -40°C to +125°C Operating Temperature
• ESD (HBM): 6kV
• Industry Standard SOT23 and SIP-3 Packages
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. “Green” Device (Note 3)
Applications
• Brushless DC Motor Commutation
• Revolution Per Minute (RPM) Measurement
• Flow Meters
• Angular and Linear Encoder and Position Sensors
• Contactless Commutation, Speed Measurement and Angular
Position Sensing/Indexing in Consumer Home Appliances, Office
Equipment and Industrial Applications
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AH3777
Document number: DS37902 Rev. 1 - 2
1 of 13
www.diodes.com
September 2015
© Diodes Incorporated
