Autonomous Constant On-Time Buck Converter With Pseudo Inductor Current Sensing for Modern High Performance Computing Devices

This paper presents an adaptive constant on-time (ACOT) buck converter for modern high-performance computing (HPC) devices. The autonomous timing/ramp-wave modulation (ATM/ARM) technique with pseudo inductor current sensing (PICS) are implemented to fulfill a smart PWM controller. With PICS technique, the modulations are capable of dynamically adjusting the on-time (TON) of the power transistor and the ramp-wave which varies according to the output loading. Besides, combining off-time (T
OFF
) modulation achieves wider operating conversion ratio. The proposed buck converter using a 130-nm BCD technology demonstrates a high transient performance and high efficiency over broad load range, significantly accomplishing the feasibility of controller architecture for modern HPC devices.