Dynamic Bias-Current Boosting Technique for Ultralow-Power Low-Dropout Regulator in Biomedical Applications

A dynamic bias-current boosting technique that concurrently enables ultralow-power operation and fast-transient behavior is presented in this brief. It is applied to an ultralow-power output-capacitor-free low-dropout regulator (LDO) to demonstrate the bandwidth extension provided during the transient periods. The proposed LDO is capable of providing 50 mA of output current with a minimum dropout voltage of 0.1 V. The ultralow-power LDO is implemented in a commercial 0.13-mu m CMOS process, with power consumption of 1.20 mu W only. Experimental results verify that both the load-and line-transient responses of the proposed LDO are significantly improved, and the settling times during load and line transients are shortened by as much as 33 and 3 times, respectively.