Design of a sensorless commutation IC for BLDC motors

This paper presents the design methodology to implement a sensorless commutation IC for brushless dc (BLDC) motors by using mixed-mode IC design technology. The developed IC can generate optimal commutation signals for BLDC motors without Hall-effect sensors and can be easily interfaced with a microcontroller or a digital signal processor (DSP) to complete the closed-loop control system. Furthermore, this IC solution requires less analog compensation circuits than other commercial motor control ICs, therefore, high maintainability and accurate control can be achieved. The proposed sensorless commutation IC is integrated in a standard digital single-poly, and four metal 0.35-mum CMOS process.