A 0.18-μm BCD Adaptive-On-Time Buck DC-DC Converter with 96.03% Peak Efficiency and 100% Duty Cycle

This paper proposes a high-efficiency adaptive-on-time buck DC-DC converter (HEAOT-Buck) capable of supporting a 100% duty cycle. The converter operates over an input voltage range of 3-18 V and provides an adjustable output voltage from 0.9 to 5.5 V, delivering up to 1 A load current. Implemented using a 0.18 µm BCD process, the chip attains a peak efficiency of 96.03%. When the load current changes from 0.1 to 1 A, the output voltage regulation remains within 0.36%, while the line regulation below 0.55%. At a switching frequency of 2.5 MHz and a 0.5 A load condition, the output voltage ripple measures at approximately 22 mV. Under a load transient from 0 to 1 A, the output voltage settles within 10 µs.