Fast transient technique (FTT) in buck current-mode DC-DC converters for low-voltage SoC systems

This paper proposes a fast transient technique (FTT) to achieve excellent transient response of current-mode buck DC-DC converters. The proposed technique combines a non-linear control and a linear control mechanism to achieve fast transient response time, low output ripples, and stable transient operation at the same time. The test chip was fabricated in UMC 0.18-mum process. Experimental results show that the transient undershoot/overshoot voltage and the recovery time are not exceed 48 mV and 10 mus, respectively.