AH3781-SA-7

AH3781 HIGH-VOLTAGE HIGH-SENSITIVITY HALL EFFECT LATCH WITH INTERNAL PULL-UP RESISTOR PRELIMINARY - CONFIDENTIAL Description Pin Assignments The AH3781 is a high-voltage, high-sensitivity Hall Effect latch IC with internal pull-up resistor designed for commutation of brushless DC motors, flow meters, linear encoders and position sensors in industrial, 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 AH3781 provides a reliable solution over the whole operating range. For robustness and protection, the device has a Zener clamp on the supply. The output has an overcurrent limit and a Zener clamp. (Top View) 3 OUTPUT GND 2 1 VDD SOT23 (Top View) The internally pulled-up 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 part marking surface is larger than the operate point (BOP) the output is 3. OUTPUT 2. GND 1. VDD switched on (pulled low). The output is held latched until magnetic flux density reverses and becomes lower than the release point (BRP). SIP-3 Features Applications • • • Bipolar Latch Operation (South Pole: On, North Pole: off) 3.0V to 28V Operating Voltage Range High Sensitivity: BOP and BRP of +25G and -25G Typical • • • Internally Pull-up Resistor on the Output Pin Output Overcurrent Limit Chopper Stabilized Design Provides Superior Temperature Stability Minimal Switch Point Drift Enhanced Immunity to Stress Good RF Noise Immunity Zener Clamp on Supply and Output Pins -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) • • • • • • • • • • • • Notes: 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 Equipments and Industrial Applications 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