Synchronous buck DC/DC converter to perform an improved switching operation by adjusting variable resistor

A DC/DC converter comprising:

• a switching controller to generate a switching signal according to a first power source;
• a switching circuit to output a waveform according to the switching signal and a second power source;
• a smoothing circuit to output a DC power according to the waveform output from the switching circuit;
• a variable resistor connected between switching unit and the first power source to adjust the first power source supplied to the switching controller;
• and
• a variable resistor controller to sense a load current of the smoothing circuit and to change a resistance of the variable resistor to generate the adjusted first power source according to the sensed load current, so that the switching controller generates a modified switching signal according to the adjusted first power source, the switching circuit outputs a second waveform according to the modified switching signal, and the smoothing circuit outputs a second DC Power according to the second waveform.

A DC/DC converter comprising:

• a switching controller to generate a switching signal according to a first power source;
• a switching circuit to output a waveform according to the switching signal and a second power source;
• a smoothing circuit to output a DC power according to the waveform output from the switching circuit;
• a controller to detect a characteristic of the smoothing circuit with respect to the output DC power and to control the switching circuit according to the characteristic of the smoothing circuit to output a first waveform having a first rising time and a first peak voltage in the first rising time, and a second waveform having a second rising time and a second peak voltage in the second rising time, as the waveform.