Digitally controlled boost converter with digital DLL based calibration

This paper presents the digitally controlled boost converter with delay-locked loop (DLL) to enhance the resolution. We propose two novel circuits: all digital ramp generator for coarse tuning and DPWM with build-in DLL for calibration. This circuit is designed in 0.35μm CMOS process. The input voltage range is from 3.3V to 4.2V with output voltage of 5V. The maximum efficiency is 90% at loading current to be 500 mA.

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