| 摘要 |
PROBLEM TO BE SOLVED: To overcome the problem that, in a power supplying system wherein power supply devices 1, 2 are connected in parallel for supplying power to a load device 3, a back-flow prevention circuit connected to the output side of the respective power supply devices 1, 2 is composed of an OR ring diode and MOSFET, and each power supply device needs two additional MOSFETs connected in reverse direction so as to prevent damage to the MOSFET in the back-flow prevention circuit when a power supply starts or the load device 3 fails, so that a large power loss occurs in the back-flow prevention circuit and the power supply system needs a large mounting area.SOLUTION: In a power supplying system that includes a plurality of power supply devices 1, 2 connected in parallel, each of which has a back-flow prevention circuit at an output side thereof and supplies power to the load device 3, a back-flow prevention circuit (Q5+R1+8) is configured by using a hetero-junction FET (HEMT) Q5. A normally-on type GaNFET is used for the hetero-junction FET (HEMT) Q5, so that the back-flow prevention circuit is further simplified. |
