A fast response adaptive DC-DC switching converter using on-chip dual-loop one-cycle control

A switching buck converter with variable output voltage using one-cycle control is presented. The control loop employs dc level shifting technique to eliminate the use of negative supply voltage. This controller accommodates both continuous and discontinuous conduction operation, and improves on existing open loop designs by adding a feedback loop for tight output voltage control. It was fabricated using a 0.51µm n-well CMOS process. The output voltage can vary from 0.9V to 2.5V, with a tracking time of 15µs for a step change of 1.2V. Efficiency is enhanced by a dynamic loss control, and a maximum efficiency of 93.7% is achieved with good line and load regulation.