Controlling a switched mode power supply with maximised power efficiency

摘要

A control circuit for a switched mode power supply (SMPS) has an input voltage reference voltage generator arranged to receive a signal indicative of an input voltage of the SMPS and is arranged to generate a reference signal directly proportional to the input voltage. An error signal generator of the control circuit is arranged to receive a signal indicative of an output voltage of the SMPS and arranged to generate an error signal based on the reference signal generated by the input reference voltage generator and based on the output voltage of the SMPS. A duty cycle control signal generator of the control circuit is arranged to generate a control signal, to control the duty cycle of the SMPS, in dependence upon the error signal.