Patent ID: 8610415

Claim:
An apparatus comprising: a charge device configured to couple an input supply node to an output supply node, wherein a resistance of the charge device is responsive to control information received at a control node of the charge switch; a first amplifier configured to compare feedback information to a current limit threshold and to modulate the control information received at the control node of the charge device using the comparison; and a current sense circuit configured to provide the feedback information, the current sense circuit including: a feedback transistor; a sense transistor configured to coupled the input supply node with a first terminal of the feedback transistor, the sense transistor having a control node coupled to the control node of the charge switch; a first feedback resistor coupled between a reference potential and a second terminal of the feedback transistor, the feedback resistor configured to provide load current information of the output supply node, wherein the feedback information includes the load current information; a second amplifier configured to compare a voltage of the output supply node to a sensed voltage at an output node of the sense transistor, the second amplifier further configured to modulate a control node of the feedback transistor using output information of the second amplifier; and a first transconductance amplifier configured to compare the voltage of the output supply node to a foldback reference voltage and to use the comparison to provide foldback information as part of the feedback information, wherein the foldback information is configured to increase the resistance of the charge device when the voltage of the output supply node falls below the foldback reference voltage.