Patent ID: 8036006

Claim:
A power supply circuit, comprising: a control circuit which outputs a control signal when an in-rush current flows; and a power-supply-resistance control circuit which supplies a current to a capacitive load; wherein the power-supply-resistance control circuit is provided in a current path between a power supply and the capacitive load, increases a resistance of the current path in response to the control signal, and reduces the resistance of the current path in response to a stop page of the control signal, wherein the control signal is output or stopped to suppress the in-rush current to a value smaller than or equal to a given value, wherein the control circuit outputs the control signal when a value of the in-rush current exceeds a preset threshold, and stops outputting the control signal when the value of the in-rush current no longer exceeds the threshold, wherein the control circuit comprises: a control signal generating circuit which generates the control signal; a hold circuit which holds the control signal output from the control signal generating circuit and continuously outputs the control signal for a given period of time, and wherein the hold circuit holds the control signal during a period in which the in-rush signal is exceeding the threshold again due to a reduction in the power-supply resistance by a stop page of output of the control signal.