An Integrated Pulse Width Modulator/Dead-time Generator with Improved Output Voltage Precision

Abstract

This paper presents an integrated pulse width modulator with dead-time generation capability. The proposed modulator can place proper dead-time around gating pulses while maintaining the correct volt-second of the output voltage on a pulse-by-pulse basis. The proposed method is suitable for digital implementation of PWM, and the required computational resource is very low. Compared to the conventional dead-time compensation by average voltage correction, the proposed method provides improved accuracy of output voltages and hence better dynamic response. Experimental results are provided to verify the proposed method. Comparisons with other dead-time generation/compensation method are also presented.