150 mA LDO with self-adjusting frequency compensation scheme

摘要

A low-drop-out regulator with dynamic biased buffers for self-adjusting frequency compensation is presented. The proposed buffer, based on gm-boost elements, keeps the second pole beyond the unity-gain frequency of the loop by dynamically changing its bias current according to the load condition. The LDO has a quiescent current of 23 ;C;A and is able to deliver 150 mA load current. With wide loop bandwidth and adequate phase margin, improved transient response with 38 mV output variation is achieved under a 0–100 mA load current switching test.