Patent ID: 7173405

Claim:
A circuit for limiting a power current from a power-controlling pass device, the power-controlling pass device coupled to a supply voltage, comprising: a sense device coupled to the supply voltage, the sense device configured to draw a sense current that is proportional to the power current; a current mirror coupled to the sense device and coupled to the supply voltage, the current mirror configured to draw a mirror current that is relative to the sense current; a resistance device coupled to the supply voltage and to the current mirror, the limiting transistor configured generate a resistor voltage potential; a limiting device coupled to the supply voltage, the power-controlling pass device, and to the resistor, the limiting device configured to limit the power current according to the resistor voltage potential; and a bias circuit that generates a bias voltage to adjust said resistance voltage to change said resistance voltage potential comprising: a first current source supplying a first current wherein said first current is substantial to current flowing through said limiting device during a short circuit, a second current source supplying a second current wherein said second current is substantially equal to current flowing through said resistance device during a short circuit, a first device that replicates said limiting device coupled to said supply voltage and said second current source, and a second device that replicates said resistance device coupled to said supply voltage and said first current source.