Commutation board for brushless motor

A board for commutation of a brushless motor having encoder means comprising a plurality of Hall-effect sensors operative for providing commutation information to a motor controller, the board being adapted to fit on the end of the brushless motor and comprising an output drive section which includes three high-side power P-channel FETs and three low-side power N-channel FETs connected to determined stator windings of the brushless motor;

• a low-side pre-drive circuit operative to selectively turn on each of the low-side FETs and a high-side pre-drive circuit operative to selectively turn on each of the high-side FETs;
• a commutation decode logic circuit;
• an oscillator connected to the commutation decode logic circuit for providing a clock signal thereto;
• and, said commutation decode logic circuit being connected to the Hall-effect sensors to receive the commutation position information from the Hall-effect sensors and being connected to the high-side and low-side pre-drive circuits for providing selection signals for selecting the appropriate power FETs for commutating the motor, the board also including an overcurrent detection and current limiting circuit connected to the low-side power FETs to monitor current through the motor.