| 摘要 |
Provided is a high-efficiency, low-cost switching power source device. This switching power source device is provided with a high breakdown voltage transistor (11), and a low breakdown voltage transistor (12). When current flows from a second node (N2) to a first node (N1), the high breakdown voltage transistor (11) is set to an on state, the low breakdown voltage transistor (12) is turned off, and the current flows to a built-in diode (12a) of the low breakdown voltage transistor (12). The current does not flow to a parasitic diode (11a) of the high breakdown voltage transistor (11), and therefore recovery current can be reduced. Moreover, a first delay circuit, which comprises resistors (51a, 51b), and a diode (51c), is connected to a gate electrode of the high breakdown voltage transistor (11), and a second delay circuit, which comprises resistors (52a, 52b), and a diode (52c), is connected to a gate electrode of the low breakdown voltage transistor (12). Therefore, the switching speed at the time of the switching operation can be finely adjusted, and reduce loss. |
