Integrated circuit driver having current limiter for brushless motor

摘要

An integrated circuit driver for a brushless motor having an encoder which includes a plurality of Hall-effect sensors operative for providing commutation information to a motor controller includes a commutation decoding section for decoding the commutation information from the Hall-effect sensors and an analog current limiter. The current limiter includes a circuit for dynamically switching the current limit values for current in the motor between a high current limit value and a low current limit value based on the average or RMS value of the motor winding current. The current limit values must be provided externally. A Hall-effect sensor quadrature encoder is provided on the integrated circuit and a selection switch allows for the selection of a quadrature output from an external optical encoder or the internal Hall-effect sensor encoder.