Frequency hopping control circuit for reducing EMI of power...

Details Frequency hopping control circuit for reducing EMI of power... Frequency hopping control circuit for reducing EMI of power...

2005-12-08

2009-08-18

Ullah, Akm E (Department: 2858)

Electric power conversion systems

Cascaded or combined, diverse conversions in which the...

C323S283000, C323S284000

Reexamination Certificate

active

07577002

ABSTRACT:
A control circuit having frequency hopping capability is used for reducing the EMI of a power supply. A switching circuit is coupled to a feedback circuit to generate a switching signal for regulating an output of the power supply. A first oscillator determines the switching frequency of the switching signal. A second oscillator is coupled to the first oscillator to modulate the switching frequency of the switching signal for reducing the EMI of the power supply. An output of the second oscillator controls the attenuation rate of the feedback signal of the feedback circuit. Therefore, even if the switching frequency is hopped, the output power and the output voltage can still be kept constant.

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