Samsung Display Co., Ltd.

Samsung Mobile Display Co., Ltd.

Sungcheon Park

Wook Su Lee

Choonyul Oh

Kyoungsoo Lee

An organic light emitting display and power supply method thereof operate an organic light emitting display panel using a high voltage EVLDD and a low voltage ELVSS supplied from a driver integrated circuit during a low power display mode. The organic light emitting display a first power supply configured to supply a first power including a first high voltage and a first low voltage, a second power supply configured to supply a second power including a second high voltage and a second low voltage, and an organic light emitting display panel configured to receive the first power from the first power supply in a standard display mode and configured to receive the second power from the second power supply in a low power display mode.

Organic light emitting display and power supply method thereof

An organic light emitting display having a DC-DC converter with freewheel diodes replaced by switches integrated into a switching controller. This way, power consumption is reduced by truly shutting down a current path when the DC-DC converter does not operate, and the size and weight of the DC-DC converter may be reduced. One embodiment of the DC-DC converter has a boost converter with a first switch coupled to a power supplier and a second switch, functioning as a freewheel diode, coupled to an organic light emitting display panel, and an inverter with a third switch coupled to the power supplier and a fourth switch, functioning as a freewheel diode, coupled to the organic light emitting display panel. A switching controller is coupled to the boost converter and the inverter. The second and fourth switches, which function as the freewheel diodes, are integrated into the switching controller.

Organic light emitting display having DC-DC converter

An organic light emitting display keeps a constant grayscale in an organic light emitting display panel even if power supplied by a power supply is changed. The organic light emitting display includes: a switching unit for selecting and outputting a first source power or a second source power as a first reference power; a comparator for comparing the first reference power with the second source power and outputting a difference value between the first reference power and the second source power; an adder for adding the difference value to an initial second reference power to output as a second reference power, such that a voltage level of the second reference power is changed when a voltage level of the first reference power is changed; and a gamma voltage generator for generating plural gamma voltages to be utilized for displaying the image on an organic light emitting display panel by utilizing the first and second reference powers.

Growing community of inventors

Yongin-si, South Korea

Sungcheon Park