Patent ID: 7075804

Claim:
A soft start circuit for a power supply comprising: an input port which is adapted to be coupled to said power supply; an output port from which a soft start output voltage is to be provided; a start-up voltage generator adapted to be coupled to said input port; a controlled output power circuit device coupled to said output port; an operational amplifier having an output coupled to said controlled output power circuit device, a first input coupled to receive a first prescribed reference voltage, and a second input coupled to monitor said output port; and a comparator having an output coupled to said start-up voltage generator, a first input coupled to receive a second prescribed reference voltage less than said first prescribed reference voltage, and a second input coupled to monitor said output port, and wherein said comparator is operative, in response to the voltage at said output port exceeding said second prescribed reference voltage, to enable said start-up voltage generator to apply a start-up voltage signal to said first input of said operational amplifier, whereupon said operational amplifier drives said output port with a soft start voltage corresponding to said start-up voltage signal.