Fast-transient capacitor-less low-dropout regulator with assistant push-pull output stage using bootstrap technique

An output-capacitor-less low-dropout regulator (LDR) with an assistant push-pull output stage using a bootstrap technique is proposed. By utilising such a technique, the proposed LDR is able to achieve a fast-transient response. The proposed LDR was implemented in a standard 0.35 μm CMOS process. Measurement results show that the undershoot of the output voltage is 375 mV at the condition of the load current switching from 1 to 200 mA at a rise time of 500 ns.