| 摘要 |
A method for controlling a switching converter is disclosed whereby the switching converter is configured to convert an input voltage into an output voltage supplied to a load in accordance with a switching signal, The switching converter is configured to operate in a pulse width modulation mode or, alternatively, in a pulse frequency modulation mode. When operating in the pulse width modulation mode, generating, as the switching signal, a pulse width modulated (PWM) signal of a pre-defined constant switching frequency. The PWM signal has a duty cycle that is regulated such that the output voltage of the switching converter matches, at least approximately, a desired output voltage under the condition that the duty cycle being regulated such that it does not fall below a predefined minimum duty cycle. The output voltage is monitored and switched over to the pulse frequency modulation mode when the output voltage exceeds a predefined first threshold. The method further comprises, when operating in the pulse frequency modulation mode, monitoring the output voltage and generating, as the switching signal, a series of pulses of a predefined constant pulse length. A pulse is generated each time the output voltage falls to a predefined second threshold and monitoring the frequency of the switching signal and switching to the pulse width modulation mode when the frequency of the switching signal exceeds a predefined frequency threshold.
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