| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power supply unit and a feeding method having a simple structure, reducing the amount of generated noise, supplying DC while preventing instantaneous disconnection in the event of power failure in an AC power supply, and supplying DC to a load while preventing excessive current from flowing through the load. SOLUTION: AC voltage supplied from an external AC power supply ACV is rectified by a rectifier RECT1, and a secondary battery B is charged when rectified voltage occurs. The AC voltage supplied by the AC power source ACV is supplied to an electrical apparatus 2. When the AC voltage generated by the AC power supply ACV reach a prescribed lower limit level, a diode D1 is reverse-biased, and the secondary battery B is not discharged. On the other hand, when the AC voltage generated by the AC power supply ACV has not reached the prescribed lower limit level, the diode D1 is forward-biased, and the secondary battery B starts discharging, and the current is supplied to the electrical apparatus 2 through the diode D1.</p> |
