LDO regulator with improved load transient performance for internal power supply

摘要

A voltage regulator includes a feedback regulation loop and a drive transistor configured to source current to a regulated output. A transient recovery circuit is coupled to the voltage regulator circuit and includes a first transistor coupled to source current into a control terminal of the drive transistor, wherein the source current is in addition to current sourced in response to operation of the feedback regulation loop. The first transistor is selectively actuated in response to a drop in voltage at the regulated output. The transient recovery circuit further includes a second transistor coupled to sink current from the regulated output. The sink current has a first non-zero magnitude in the quiescent operating mode of the regulator circuit. In response to an increase in voltage at the regulated output, the operation of the second transistor is modified to increase the sink current to a second, greater, non-zero magnitude.