Adaptive sampling circuit and a control circuit for detecting a voltage transformer demagnetization

The present invention discloses an adaptive sampling circuit and a control circuit for detecting a voltage of demagnetization of the transformer, which comprises a sample holding unit, and a signal generation circuit. A sample-hold unit is coupled to the transformer, and the sampled voltage transformer according to a demagnetizing a sample signal to generate a feedback signal. Sampling signal generation circuit generates an excitation signal according to the voltage transformer, a voltage transformer is demagnetized, a switching signal and a control code. Degaussing voltage sample signal for sampling; associated with a feedback signal to a power converter output voltage; switching signal is a feedback signal is generated, to switch and adjust the output transformer of the power converter. Adaptive sampling circuit of the invention for accurately measuring voltage transformer demagnetized, without limitation transformer design.