| 摘要 |
<P>PROBLEM TO BE SOLVED: To resolve a problem that a power transformer, when it is in continuous mode drawing a higher-load current than a steady state current, is heated to a high temperature exceeding an upper standard temperature limit. <P>SOLUTION: A power supply apparatus comprises a thermistor mounted in a time constant circuit determining the maximum on-time of a main switching FET, or a power supply apparatus that has an overcurrent detection circuit comprises a thermistor in its overcurrent detection unit. In addition, the thermistor is arranged near or in contact with a power transformer and configured to change its resistance values depending on the temperature of the transformer so that it can behave as in the case that the maximum on-time is shortened or the overcurrent detection is made. <P>COPYRIGHT: (C)2012,JPO&INPIT |
