A Ripple Control Dual-Mode Single-Inductor Dual-Output Buck Converter With Fast Transient Response

A novel integrated single-inductor dual-output buck converter based on the ripple control technique is presented, which can provide two independent output voltages (1.2 and 1.8 V) only using one inductor. The peak current common-mode and ripples compare differential-mode are adopted to improve the system transient response. The converter can automatically switch between pulsewidth modulation and pulse-skip modulation to improve the light load conversion efficiency. The proposed converter has been fabricated in a 0.18 μm 1P6M CMOS process. The experimental results show the transient response time is about 10 μs and the cross-regulation is less than 0.05 mV/mA while the load current suddenly changes 200 mA. In general, the conversion efficiency at light load is above 86% and the peak efficiency at the full load can achieve 93.5%.