Fine Resolution DPWM Circuit for High Frequency Digital Control DC-DC Converter

The switching power supply is required the small size and light weight. Generally, it is possible to miniaturize the passive element by increasing the switching frequency of the switching power supply circuit. Also, it leads to the reduction of the entire size and weight reduction. However, the clock frequency has to be further increased in order to use the digital control switching power supply at high switching frequencies because the PWM signal is generated by counting the clock signal. As a result, the CMOs structure increases power consumption as the frequency rises. Further, the cost of the control circuit itself increases. Therefore, in this paper, the DPWM signal generator with the simple structure that provides the better resolution than the conventional method is proposed. In the simulation, the proposed method can improve the resolution of the PWM signal by 3 bits. The validity of the proposed method is confirmed.