AH278

HIGH VOLTAGE HALL EFFECT LATCH General Description Features Data Sheet AH278 The AH278 is an integrated Hall sensor with output driver designed for electronic commutation 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 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 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 · 500mA (avg) Output Sink Current · Build in Protection Diode for Reverse Power Connecting · -20oC to 85oC 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 · Communications Facilities · Industrial Equipment AH278 is available in TO-94 (SIP-4L) package. Nov. 2009 Rev. 1. 4 TO-94 Figure 1. Package Type of AH...