On-chip compensated error amplifier for voltage-mode buck converters

摘要

An on-chip compensated error amplifier in a voltage-mode buck converter is proposed in the paper. The compensated error amplifier is composed of two blocks, unit gain zero generation block and gain block, realizing phase shift and gain of the feedback loop, respectively. Compared to conventional type III compensated error amplifier in voltage-mode buck converter, the proposed circuit has much smaller passive component values, enabling full integration of the voltage mode buck converter in SoC. The converter is designed in 0.13µm CMOS process, operating typically at 1.5 MHz pulse width modulation (PWM). The simulation results show the converter with on-chip compensated error amplifier achieves both 0.3% load regulation and 10µs load step response time for load step between 200mA and 700mA.