| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power supply unit with an overvoltage protection circuit, capable of accommodating a high withstand voltage test using a small-sized and inexpensive constant-voltage element. <P>SOLUTION: The power supply unit includes a surge noise filter circuit 20 which absorbs a transient overvoltage generated at a power supply line. The surge noise filter circuit 20 includes a constant-voltage element 10 and a first capacitor 11 connected in series between the power supply line and the ground 2, and a second capacitor 12 connected in parallel to the constant-voltage element 10. <P>COPYRIGHT: (C)2012,JPO&INPIT |
