Adaptive on-chip power supply with robust one-cycle control technique

In this paper, an integrated adaptive-output switching converter is proposed. The design employs a one-cycle control for fast line regulation and a single outer loop for tight load regulation and fine tuning. A switched-capacitor integrator is introduced to the one-cycle control to obtain positive integration with a single positive power supply, allowing a standard low-cost CMOS fabrication process. To improve the efficiency, a dynamic loss control technique is presented. The converter was designed and fabricated with 0.35 μm N-well CMOS process. With a supply voltage of 3 V, a voltage ripple of less than ± 20 mV is measured. The maximum efficiency is 92% with a load power of 475 mW. The converter exhibits a tracking speed of 23.75 μs/V for both start-up and reference voltage transitions. The recovery time for a 20% load change is approximately 9.5 μs.