General Description

The AH277A is an integrated Hall sensor with output driver designed for electronic commutation of brush less DC motor applications. The device includes an on chip Hall sensor for magnetic sensing, an amplifier that amplifies the Hall voltage, a Schmitt trigger to provide switching hysteresis for noise rejection, a temperature compensation circuit to compensate the temperature drift of Hall sensitivity and two complementary open-collector drivers for sinking large load current. It also includes an internal band-gap regulator which is used to provide bias voltage for internal circuits.

Features

· On-Chip Hall Sensor

· 3.5V to 16V Supply Voltage

· 400mA (avg) Output Sink Current

· Reversed Supply Voltage Protection

· -20oC to 85oC Operating Temperature

· Low Profile TO-94 (SIP-4L) Package

· ESD Rating: 300V (Machine Model)

Applications· Dual-Coil Brushless DC Motor

· Dual-Coil Brushless DC Fan

· Revolution Counting

· Speed Measurement