| 摘要 |
PURPOSE:To protect a capacitor from causing overcharge and, at the same time, to protect a discharge circuit by providing plural discharge circuits and discharging the plural discharge circuits alternately. CONSTITUTION:In a solar battery timepiece made by connecting a capacitor 2c charged from a solar battery 2a through a diode 2b in parallel to a clock load 2d, a discharge circuit 2k' is provided in parallel with a discharge circuit 2k, and a discharge switching controlling circuit 2m to operate the two discharge circuits 2k, 2k' alternately is provided. When an overcharge detecting circuit 2j detects overcharge of the capacitor 2c and outputs an overcharge detection signal P2j, the circuit 2m outputs controlling signals P2m, P2m' alternately, and discharge the circuits 2k, 2k'. Thus, overheat of the discharge circuit due to Joule heat can be prevented, and destruction of the discharge circuit for protec tion, prevention of overcharge of the capacitor due to overheat can be prevented.
|
