AH278 Datasheet | BCD Semiconductor

Description Features Data Sheet AH278 The AH278 is an integrated Hall sensor with output driver designed for electronic mutation of brushless DC motor applications. The device includes an onchip Hall sensor for magnetic sensing, an amplifier that amplifies the Hall voltage, a Schmitt trigger to provide switching hysteresis for noise rejection and two plementary 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 and allows a wide operating supply voltage ranges. Placing the device in a variable magnetic field, if the magnetic flux density is larger than threshold BOP, the pin DO will be turned low (on) and pin DOB will be turned high (off). This output state is held until the magnetic flux density reverses and falls below BRP, then causes DO to be turned high (off) and DOB turned low (on). - On-Chip Hall Sensor - 4V to 30V Supply Voltage - 500m A (avg) Output Sink Current - Build in Protection Diode for Reverse Power Connecting - -20o C to 85o C Operating Temperature - Low Profile TO-94 (SIP-4L) Package - Build in Over Temperature Protection Function - ESD Rating: 300V(Machine Model) Applications - 12V/24V Dual-Coil Brushless DC Motor/Fan - Power Supply and Switchboard - munications Facilities - Industrial Equipment AH278 is available in TO-94 (SIP-4L) package. Nov. 2009 Rev. 1. 4 TO-94 Figure 1. Package Type of AH278 BCD Semiconductor Manufacturing Limited 1 HIGH VOLTAGE HALL EFFECT LATCH Pin Configuration Z4 Package (TO-94) 4 3 2 1 GND DOB DO VCC Figure 2. Pin Configuration of AH278 (Front View) Data Sheet AH278 Pin Description Pin Number 1 2 3 4 Pin Name VCC DO DOB GND Supply voltage Output 1 Output 2 Ground Function Nov. 2009 Rev. 1. 4 BCD Semiconductor Manufacturing Limited 2 HIGH VOLTAGE HALL EFFECT LATCH Functional Block Diagram VCC 1 Regulator Over-Temperature...