Control circuit of power converter and control method thereof

A control circuit of a power converter, comprising:

• an error amplifying circuit, coupled to an output terminal of the power converter and providing a digital error signal;
• a controller, storing a plurality of working parameters, wherein when the controller receives a first external control command, the controller provides a first working parameter corresponding to the first external control command;
• a digital filter, coupled to the controller and the error amplifying circuit, and generating a current digital compensation value according to the first working parameter and the digital error signal;
• and
• a digital pulse width signal modulator, coupled to the digital filter and generating a pulse width modulation signal according to the current digital compensation value,
• wherein when the controller receives a second external control command, the controller provides a second working parameter corresponding to the second external control command, the controller calculates a transition value according to the second working parameter and the current digital compensation value, and the controller then provides the second working parameter and the transition value to the digital filter,
• wherein the controller comprises:
• a decoder, receiving the second external control command and generating an indication signal according to the second external control command;
• a memory, coupled to the decoder and the digital filter, and storing the working parameters, wherein the memory output one of the working parameters as the second working parameter according to the indication signal;
• and
• a computing unit, coupled to the memory and the digital filter, and calculating the transition value according to the second working parameter and the current digital compensation value.