| 摘要 |
<p>A switch mode power supply comprises a drive circuit (7) for generating first and second switching signals in response to first and second input signals of different frequencies, and a switching regulator (9) for generating one or more regulated power supply output voltages in response to the first and second switching signals. The power supply further comprises a control circuit (3,4,6,10,15) for determining, in response to the first and second input pulse signals, a first frequency range containing the frequencies of the first and second input signals when respectively multiplied by first and second integer multiples that is narrower than a second frequency range containing the frequencies of the first and second input signals when each multiplied by a common integer multiple. The control circuit (3,4,6,10,15) configures the drive circuit (7) to generate the first switching signal at a frequency which is the first integer multiple of the frequency of the first input pulse signal and the second switching signal at a frequency which is the second integer multiple of the frequency of the second input pulse signal in such a manner that the frequencies of the first and second switching signals are within the first range. <IMAGE></p> |
