Texas Instruments Incorporated
LOAD CURRENT BASED DROPOUT CONTROL FOR CONTINUOUS REGULATION IN LINEAR REGULATORS

Abstract:

In a linear regulator system, a pass element has a control terminal, an input terminal and an output terminal. The pass element is configured to provide an output voltage at the output terminal based on: an input voltage at the input terminal; and a control signal at the control terminal. A dropout error amplifier has an error output and first and second inputs. The first input is coupled to the output terminal, and the error output is coupled to the control terminal. The dropout error amplifier is configured to provide a dropout control signal at the error output based on a comparison between: the output voltage at the first input; and a dropout reference voltage at the second input. The pass element is configured to regulate the output voltage at the dropout reference voltage, responsive to the dropout control signal.