Driver circuit for switching switch according to capacitor voltage

A driver circuit for switching switch according to capacitor voltage, utilized to control an average current to drive a load circuit under a continuous conduction mode (CCM), the load circuit including a load resistor which has one end grounded and another end receiving a load resistor voltage, and the driver circuit comprising:

• a first switch, which has a first switching connection end and a second switching connection end;
• a first current module, which has a first current output end electrically connected to the first switching connection end, electrically connected to the load resistor to generate a variable current according to the load resistor voltage;
• a second current module, having a second current output end electrically connected to the first switching connection end and the first current output end of the first current module to generate a constant current;
• a first capacitor, having one end electrically connected to the second switching connection end and another end grounded;
• a second switch, having a third switching connection end and a fourth switching connection end, and the third switching connection being electrically connected to the first capacitor and the second switching connection end;
• a second capacitor, having one end electrically connected to the fourth switching connection end and another end grounded;
• a constant voltage module, electrically connected to the second capacitor and the fourth switching connection end to provide a constant voltage supplied to the second capacitor;
• and
• a processing module, electrically connected to the first capacitor, the second capacitor, and gates of the first switch and the second switch to conduct one of the first switch and the second switch;
• wherein, as the processing module conducts the first switch and turns off the second switch and the variable current is greater than the constant current, a charging current is generated based on difference between the variable current and the constant current to charge the first capacitor, and the variable current gradually decreases attending with increasing of the load resistor voltage;
• as the variable current is smaller than the constant current, a discharging current, which is identical to the difference between the constant current and the variable current, is generated by the first capacitor, and as the first capacitor is discharged to have a first capacitor voltage of the first capacitor identical to a second capacitor voltage of the second capacitor, the processing module is triggered to turn off the first switch and conduct the second switch so as to control the average current to drive the load circuit.