Patent Document ID: 20060022660
Application ID: 11189607
Patent Flag: 0

Claim One:
1. A constant voltage circuit converting an input voltage into a predetermined constant voltage in accordance with an externally input control signal and outputting the predetermined constant voltage, the constant voltage circuit comprising: a constant voltage generator circuit part configured to convert the input voltage into the predetermined constant voltage in accordance with the control signal and output the predetermined constant voltage; a first capacitor connected to an output end of the constant voltage generator circuit part outputting the constant voltage; a second capacitor configured to charge the first capacitor; and a switch circuit part configured to control charging and discharging of the second capacitor in accordance with the control signal, wherein the switch circuit part charges the second capacitor by applying the input voltage thereto and blocks the discharging of the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to stop outputting the predetermined constant voltage by the control signal; and the switch circuit part stops applying the input voltage to the second capacitor and charges the first capacitor by releasing an electric charge stored in the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to start outputting the predetermined constant voltage by the control signal.