DC-DC converter and organic light emitting display device using the same

An organic light emitting display device comprising:

• a display unit for displaying an image in response to a data signal, a scan signal, a first power of a first power source and a second power of a second power source;
• a data driver for generating and outputting the data signal;
• a scan driver for generating and outputting the scan signal;
• a DC-DC converter for generating and outputting the first power of the first power source and the second power of the second power source;
• and
• a controller for outputting a control signal to control the DC-DC converter,
• wherein the DC-DC converter comprises:
• a buck-boost circuit for generating and outputting the second power of the second power source by utilizing an input voltage, the buck-boost circuit being configured to adjust and output the voltage level of the second power source in accordance with a voltage level of the input voltage;
• a boost circuit for generating and outputting the first power by boosting the input voltage;
• and
• a controller configured to control the buck-boost circuit,
• wherein the buck-boost circuit comprises a first coil coupled between a first node and a ground;
• a first capacitor having first and second electrodes, the first electrode being coupled to the first node;
• a first switch coupled between the first node and an input terminal;
• a second switch coupled between the second electrode of the first capacitor and the ground;
• and a third switch coupled between the second electrode of the first capacitor and a first output terminal.

A DC-DC converter comprising:

• a buck-boost circuit for generating and outputting a power of a power source using an input voltage, the buck-boost circuit being configured to adjust and output the voltage level of the power of the power source in accordance with the voltage level of the input voltage;
• and
• a controller configured to control the buck-boost circuit,
• wherein the buck-boost circuit comprises a first coil coupled between a first node and a ground;
• a first capacitor having first and second electrodes, the first electrode being coupled to the first node;
• a first switch coupled between the first node and an input terminal;
• a second switch coupled between the second electrode of the first capacitor and the ground;
• and a third switch coupled between the second electrode of the first capacitor and a first output terminal.