| 摘要 |
PURPOSE:To prevent the deterioration of efficiency even when a load is small, in a system having a plurality of switching power supplies. CONSTITUTION:An error signal is generated in a master circuit 1 by an amplifier 3 in accordance with an error between a voltage supplied to a common load and a reference voltage. An ON-pulse is generated by a comparator and a saw tooth generating circuit in respective slave circuits 5, 15 in accordance with the error signal and the like whereby an electric power is supplied to the common load. The ON-pulse is restricted in respective slave circuits by an AND circuit to control a switching power supply into inactive condition. According to this method, the switching power supply can be controlled individually by respective slave circuits and, therefore, efficiency will never be deteriorated even if the load is small when one of the switching power supplies is controlled so as to be inactive. |
