Systems and methods for providing power to pulse-width-modulation controllers of power converters during normal operation

A controller for a power converter, the controller comprising:

• a first terminal;
• a second terminal connected to a capacitor and biased to a voltage;
• a voltage detector configured to receive the voltage from the second terminal and generate a detection signal based at least in part on the voltage;
• and
• a charging controller configured to receive the detection signal and generate a first control signal based at least in part on the detection signal;
• wherein the voltage detector is further configured to:
• detect that the voltage has decreased to a first predetermined threshold;
• and
• generate the detection signal indicating that the voltage has decreased to the first predetermined threshold;
• wherein the charging controller is further configured to:
• in response to the detection signal indicating that the voltage has decreased to the first predetermined threshold, generate the first control signal indicating that a charging current is to be generated, the charging current configured to charge the capacitor associated with the voltage;
• wherein the voltage detector is further configured to:
• detect that the voltage has increased to a second predetermined threshold;
• and
• generate the detection signal indicating that the voltage has increased to the second predetermined threshold;
• wherein the second predetermined threshold is larger than the first predetermined threshold.