A Voltage-Mode DC-DC Converter with Enhanced Transient Responses

This paper presents the design technique using a charge-pump circuit for enhancing the transient responses of a voltage-mode DC-DC converter. Although there is no need for additional sensing circuitry for a voltage-mode DC-DC converter, extensive frequency compensation scheme should be critical for stable operations. This converter shows slow transient responses with respect to variations of input voltage and load current. In this paper, a charge-pump circuit is added to the compensating circuit for faster responses. The proposed method is verified in hardware implementation where the voltage-mode DC-DC buck converter is fabricated in a 0.35-um CMOS technology.