A Novel Sensorless Control ASIC for Brushless DC Motor

A novel BLDCM commutation control ASIC is designed and implemented. This paper designs a novel commutation control system, which only detects zero crossing points of back EMF from two phases, and obtains the other commutation points by piecewise prediction algorithm, and designs adaptive threshold control algorithm for filtering the commutation interference signal. The novel method not only simplifies the circuit but also increases the stability of the system. The commutation control part has been designed as ASIC based on UMC 0.18um 1P6M Mixed-Mode 1.8V Twin-Well technology. The test results of control system based on ASIC show that the motor runs steadily and the algorithm is effective.