A high-speed DC-DC converter with high efficiency at wide loading range

This paper presents a high-speed DC-DC converter with the adaptive DCM controller and the switch-scaling circuit using TSMC 0.18μm CMOS process. The input voltage is 1.8V and the output voltage is 1.2V. The maximum loading is 300mA and the required passive components are at nano-scale. The proposed DC-DC converter has over 80% efficiency at loading range from 50mA to 300mA. The output ripple is below 10% of the output voltage at all loadings. To minimize the power consumption, a low-power and adaptive DCM controller is proposed to increase the efficiency and also reduce the output ripple when the loading is below 150mA. When the loading is over 200mA, the switch-scaling circuit will turn on the extra power MOS to keep the efficiency. The switching frequency of the proposed converter changes from 200kHz to 50MHz, depending on the loading. The loading boundary between proposed DCM and CCM control is 150mA.

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