A Fast-Response BUCK Converter with Adaptive Detect and Transient Enhancement Techniques

Abstract

This paper presents a fast-response BUCK converter with adaptive transient detect technique (ATDT) and transient enhancement technique (TET). In order to reduce output overshoot and undershoot voltages and achieve shorter recovery time after load change, an adaptive transient detect module is adopted to determine one-shot transient response time, duty cycle will be set to 100% or 0% instantaneously and regulation speed of compensation capacitor voltage will be also enhanced during this time. Besides, oscillation issue is effectively avoided with proposed TET. The presented fast-response BUCK has been implemented in a 0.35μm BCD process, whose verified results are provided to demonstrate the stability and fast response of proposed converter. Compared with conventional BUCK converter, the transient response time is speeded up by more than 2.4X, and the overshoot voltage is shrunk by 0.64X while achieving 0.42X undershoot voltage.