Patent ID: 7498864

Claim:
An electronic component comprising: a first transistor having a first current-carrying electrode coupled to a first node, a second current-carrying electrode coupled to a second node, and a control electrode, wherein the first node is coupled to a voltage output of a power supply and the second node is coupled to a voltage supply input of an electronic device; a differential circuit having a first input coupled to the first node, a second input coupled to the second node, and an output to provide a first voltage based on a voltage difference between the first node and the second node, the differential circuit comprising: a first operational amplifier having a first signal input, a second signal input, a first voltage supply input coupled to a first voltage reference, a second voltage supply input coupled to a second voltage reference, and an output; a first resistive element having a first electrode coupled to the first node and a second electrode coupled to the first signal input of the first operational amplifier; and a second resistive element having a first electrode coupled to the second signal input of the first operational amplifier and a second electrode couple to the output of the first operational amplifier; a comparator circuit having a first input coupled to the output of the differential circuit, a second input coupled to the second node, and an output to provide a second voltage based on a comparison of a voltage at the second node and the first voltage, the comparator comprising a second operational amplifier having a first signal input coupled to the output of the first operational amplifier, a second signal input coupled to the second node, a first voltage supply input coupled to the first voltage reference, a second voltage supply input coupled to the second voltage reference, and an output coupled to the first input of the switch circuit; and switch circuitry having a first input coupled to the output of the comparator circuit, a second input to receive an enable signal, and an output coupled to the control electrode of the first transistor, the output to provide a third voltage responsive to the second voltage and responsive to the enable signal, the switch circuitry comprising: a second transistor having a first current-carrying electrode coupled to the first voltage reference and coupled to the control electrode of the first transistor, a second current-carrying electrode coupled to the second voltage reference, and a control electrode; a third resistive element having a first electrode coupled to the output of the second operational amplifier and a second electrode coupled to the control electrode of the second transistor; and a third transistor having a first current-carrying electrode coupled to the second voltage reference, a second current-carrying electrode coupled to the control electrode of the second transistor, and a control electrode to receive the enable signal.