| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a charger/discharger that reduces cost and footprint, and a power supply device using the charger/discharger. <P>SOLUTION: The power supply device includes a rectifier 2 which converts ac power input from a commercial power supply 1 into dc power, to be supplied to a load 5, and the charger/discharger 4 composed of a step-down circuit 6 and a switching circuit 7. The charger/discharger 4 receives power output from the rectifier 2 to charge a battery pack 3 when the commercial power supply 1 is enabled, or receives power output from the battery pack 3 to supply power to the load 5 when the commercial power supply 1 fails. The step-down circuit 6 is composed of a switching element 10, a reactor 11, a capacitor 12, a diode 13, and a control unit 14. The step-down circuit 6 steps down input power to output the stepped down power through a switching operation caused by a PWM (Pulse Width Modulation) signal sent from the control unit 14 to the switching element 10. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
