| 摘要 |
This invention relates to an apparatus for controlling a switching frequency of an SMPS transformer for a video display appliance. There are problems in the conventional apparatus for controlling the switching frequency of an SMPS that only a switching noise generated during the switching-on can be removed, that a complicated construction involves difficulties in manufacturing, and that the heat generated from the switching of the SMPS transformer and switching transistor obstructs the normal operation of the other components. To solve the above problems, the apparatus for controlling the switching frequency of the SMPS transformer according to the invention having a means for generating the switching frequency of the SMPS transformer by dividing a horizontal frequency using a chip select signal (CS), which is output from the control section when a horizontal frequency is in a constant level above, controls the switching frequency of the SMPS transformer with the duty of 50??5 percent, and therefore can remove not only the noise generated at the switching-on time of the SMPS transformer but also the noise at the switching-off time.
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