Patent ID: 7199552

Claim:
A control circuit apparatus comprising: a voltage converter which uses a thin film choke coil for converting a voltage of power to be supplied to a load in a subsequent stage, from a first voltage to a second voltage; a constant current circuit for maintaining a current value of power supplied at said second voltage from said voltage converter at a predetermined current value, irrespective of power consumption in said load; a calculation circuit for calculating a current value of power consumed in said load; and a charging battery, which is chargeable with a portion of power supplied from said voltage converter or which supplies power to said load, wherein: if said current value of power consumption calculated by said calculation circuit is smaller than said predetermined current value, said constant current circuit makes said charging battery receive power corresponding to a difference between said predetermined current value and said current value of power consumption thereby charging said charging battery; and if said current value of power consumption calculated by said calculation circuit is greater than said predetermined current value, said constant current circuit makes said charging battery to supply power corresponding to the difference between said predetermined current value and said current value of power consumption.