Apparatus for preventing capacitor charger from overcharging and method thereof

A method for controlling a charging circuit, the method comprising:

• comparing a voltage level with a reference voltage level to generate a first indication signal, wherein the voltage level corresponds to an output voltage of the charging circuit;
• comparing a control value with a threshold value to generate a second indication signal;
• generating a control signal according to the first indication signal and the second indication signal, the control signal for turning the charging circuit on and off;
• and
• generating the control value according to the control signal.

An apparatus for controlling a charging circuit, the apparatus comprising:

• a first detector coupled to the charging circuit, the first detector for detecting a voltage level at a first time and generating a first indication value corresponding to the voltage level at the first time, wherein the voltage level corresponds to an output voltage of the charging circuit;
• a second detector coupled to the charging circuit, the second detector for detecting the voltage level at a second time after the first time and generating a second indication value corresponding to the voltage level at the second time;
• and
• a controller coupled to the charging circuit, the first detector, and the second detector, the controller for receiving the first and second indication values, and further for generating a control signal according to the first and second indication values for turning the charging circuit on and off.

A method for controlling a charging circuit, the method comprising:

• detecting a voltage level at a first time and generating a first indication value corresponding to the voltage level at the first time, the voltage level corresponding to an output voltage of the charging circuit;
• detecting the voltage level at a second time after the first time and generating a second indication value corresponding to the voltage level at the second time;
• and
• generating a control signal according to the first indication value and the second indication value for turning the charging circuit on and off.