ATS477

ATS477 that integrates Hall sensor with output drivers is designed for electrical commutation of brush-less DC motor application. The device includes on-chip Hall voltage generator for magnetic sensing, the error amplifier that amplifies the Hall voltage, a comparator that is to provide switching hysteresis for noise rejection, the bi-direction drivers for sinking and driving large current load, and the frequency generator (FG) that provides a signal proportional to rotation speed. Internal bandgap regulator is used to provide temperature compensated bias for internal circuits and allows a wide operating supply voltage range. Built-in protection circuit and output shunt Zener diodes were applied for protecting output drivers during operating.

If a magnetic flux density is larger than threshold Bop, DO is turned to sink and DOB is turned to drive. The output state is held until a magnetic flux density reversal falls below Brp causing DO to be turned to drive and DOB turned to sink. ATS477 is rated for operation over-temperature range from -20  to 85 and voltage range from 3.5V to 20V. The devices are available in low cost die forms or rugged SIP-4L and power SOP-7L packages.