| 摘要 |
<p>A rectifier circuit for an AC generator based upon the electromagnetic conversion and an overcharge-preventing circuit are combined together as shown in (Fig. 5A), in order to obtain, in a small number of diodes, the electric power generating performance equivalent to that of the diode bridge, thus making it possible to reduce both the size of the limiter Tr and the consumption of electric power by the circuit. A resistor is connected in series with a capacitor so that a booster circuit is started with a predetermined capacitor voltage. Using Tr for short-circuiting, furthermore, the Tr for short-circuiting is turned on under the boosting condition, whereby the series resistance component is cancelled to secure charging performance. Further, the booster circuit consists of a multiplicity of stages to enable the watch to be driven over a wide range of voltages. The boosting magnification is changed by detecting the voltages of auxiliary capacitors, thus making it possible to change the setpoint voltage and to expand the booster circuit. By adjusting the sampling timing for voltage detection at the moment the boosting operation is to be started and for voltage detection at the moment the boosting magnification is to be changed, furthermore, it becomes possible to start the booster circuit without fail.</p> |
