| 摘要 |
PROBLEM TO BE SOLVED: To sufficient utilize electric energy even using a power source having non-flat discharge characteristic by repeatedly changing the connection between a capacitor and a capacitor for elevating voltage and charging other capacitor. SOLUTION: Electric power generated by irradiating a solar battery with light is charged in a electric double layer capacitor. When the generated voltage in the battery 1 at this moment becomes over a rated voltage, a limiter circuit 2 operates to terminate charging. The power charged in the capacitor 4 is charged in a capacitor 6 by a multi-step elevation charging circuit 5. If the voltage of the capacitor 4 is 1.2V or more, the circuit 5 functions so that the capacitors 4 and 6 are the same voltage. The voltage of the power source capacitor 6 of the watch is maintained at 0.9V or more as function termination voltage so as to extend functioning time to use to 0.3 to 1.8V and effectively use the energy accumulated in the capacitor 4. |
