Electronic circuitry, power converter, and signal transmission method

A power converter for supplying electric power to a load apparatus, comprising:

• a first switch element having one end connected to the load apparatus;
• a second switch element having one end connected to the other end of the first switch element;
• a detection circuit configured to detect an input signal including a voltage at the one end of the second switch element and a voltage at the other end of the second switch element, the input signal being a differential signal;
• a first conversion circuit configured to convert the input signal into a first signal having a frequency according to a first clock signal;
• a first electromagnetic field coupler having a first terminal and a second terminal, and configured to transmit the first signal received at the first terminal to the second terminal as a second signal via a first isolation element including a capacitance;
• a second conversion circuit configured to convert the second signal into an output signal having a frequency according to the input signal based on the first clock signal;
• and
• a first charge and discharge circuit configured to charge or discharge the capacitance of the first electromagnetic field coupler from at least one of the first terminal and the second terminal in response to a voltage of a direct current component of the first signal fluctuating, to suppress a fluctuation of a voltage of a direct current component of the second signal.

A signal transmission method comprising:

• converting an input signal into a first signal having a frequency according to a first clock signal, the input signal being a differential signal;
• transmitting the first signal as a second signal via a first isolation element including a capacitance;
• converting the second signal into an output signal having a frequency according to the input signal based on the first clock signal;
• and
• charging or discharging the capacitance when a voltage of a direct current component of the first signal fluctuates, to suppress a fluctuation of a voltage of a direct current component of the second signal.