Design of a Capacitor Less Low Dropout Regulator for Portable Devices

A capacitor less low dropout linear regulator (LDO) with a capacitor multiplier circuit is proposed to replace the large external capacitor. The large external capacitor is replaced with a capacitor circuit that has 1000 multiplication factors and it is attached to the output nodes of the regulator. The capacitor-less LDO is designed for an output voltage of 1.1 V for a given supply voltage of 1.8 V using 180 nm CMOS technology. The capacitor less LDO responds in a range of 1–30 mA for load current change with a dropout voltage of 56 mV. The line and load regulations achieved are 0.23 mV/V and 0.3 mV/mA respectively.