Switching device with separated driving signal input and driving circuit of the same

In an equivalent power source for supplying a source current, an input-separated switching device driving circuit comprising:

• an input-separated switching device including a main switching device for switching a load current portion of the source current based on a first driving signal applied to a first driving signal input, and a sense switching device for switching another portion of the source current based on a second driving signal applied to a second driving signal input in order to check the intensity of the load current;
• a current sensor for forming a sensing voltage to check the intensity of the load current using current flowing to the sense switching device, the current sensor having one terminal thereof connected to the current output of the sense switching device;
• and
• a current ratio compensator for applying the sensing voltage to the second driving signal input, the current ratio compensator having a first terminal connected to one terminal of the current sensor, and a second terminal connected to the second driving signal input.

In an equivalent power source for supplying a source current, an input-separated switching device driving circuit comprising:

• an input-separated switching device including a main switching device for switching a load current portion of the source current based on a first driving signal applied to a first driving signal input, and a sense switching device for switching another portion of the source current based on a second driving signal applied to a second driving signal input in order to check the intensity of the load current;
• a current sensor for forming a sensing voltage to check intensity of the load current using current flowing to the sense switching device, the current sensor having one terminal thereof connected to a current output of the sense switching device;
• and
• a current ratio compensator for reducing a voltage applied to the first driving signal input by way of the sensing voltage, the current ratio compensator having a first terminal connected to one terminal of the current sensor, and a second terminal connected to the first driving signal input.

In first and second control signals opposite to each other in truth value, an input-separated switching device driving circuit comprising:

• an input-separated switching device including a main switching device for switching a load current portion of a source current, and a sense switching device for switching another portion of the source current in order to check intensity of the load current;
• a first delay circuit receiving the second control signal to delay a time, and generating a delayed second control signal;
• a main switch driver for switching on the main switching device based on the first control signal, and switching off the main switching device with a delay based on the second control signal output from the first delay circuit;
• a second delay circuit receiving the first control signal to delay a time, and generating a delayed first control signal;
• a sense switch driver for switching on the sense switching device with a delay based on the first control signal output from the second delay circuit, and switching off the sense switching device based on the second control signal;
• and
• a current sensor for forming a sensing voltage to check the intensity of the load current using current flowing to the sense switching device, the current sensor having one terminal thereof connected to a current output of the sense switching device.