Patent ID: 7535691

Claim:
An in-rush current limiting circuit, comprising; a power switch having a first terminal, a second terminal and a third terminal; a diode having an anode and a cathode, the anode of the diode coupled to the first terminal of the power switch; a current source circuit including first and second terminals, the second terminal of the current source circuit coupled to the second terminal of the power switch; a capacitor having first and second terminals, wherein a control voltage across the capacitor is responsive to a rate of change of voltage between the first and second terminals of the power switch, the first terminal of the capacitor coupled to a first input terminal of the in-rush current limit circuit and the second terminal of the capacitor coupled to the first terminal of the current source circuit, the second terminal of the current source circuit coupled to a second input terminal of the in-rush current limit circuit wherein the second terminal of the power switch is coupled to the second input terminal of the in-rush current limit circuit and the third terminal of the power switch is coupled to be responsive to a voltage across the current source circuit and in response to the control voltage of the capacitor.