THREE-PHASE POWER MOSFET CONTROLLER

The A3933SEQ is a three-phase MOSFET controller for use with bipolar brushless dc motors. It drives all n-channel external power FETs, allowing system cost savings and minimizing r(DS)on power loss. The high-side drive block is implemented with bootstrap capacitors at each output to provide the floating positive supply for the gate drive. The high-side circuitry also employs a unique “intelligent” FET monitoring circuit that ensures the gate voltages are at the proper levels before turn-on and during the ON cycle. This device is targeted for

applications with motor supplies from 12 V to 28 V.

FEATURES ANDBENEFITS

■Drives External N-Channel FETs

■Intelligent High-Side Gate Drive

■Selectable Coast or Dynamic Brake on Power Down

■Adjustable Dead Time for Cross-Conduction Protection

■Selectable Fast or Slow Current-Decay Modes

■Internal PWM Peak Current Control

■Reset/Coast Input

■120°Hall Commutation with Internal Pullup

■Internal 5-V Regulator

■Low-Side Synchronous Rectification

■Direction Control

■PWM Speed-Control Input

■Fault-Diagnostic Output

■Under-Voltage Protection