Samsung Display Co., Ltd.

Siduk Sung

Kihyun Pyun

Dae-Sik Lee

Songyi Han

Sanghyun Lee

Keunoh Kang

Dae-sik Lee

An organic light-emitting diode (OLED) display device includes a display panel including a plurality of pixels, the plurality of pixels being grouped into a plurality of pixel blocks, a nonvolatile memory configured to store previous accumulated block degradation information for the plurality of pixel blocks up to a previous driving period, a controller configured to calculate current block degradation information for the plurality of pixel blocks in a current driving period, to calculate current accumulated block degradation information for the plurality of pixel blocks up to the current driving period by adding the current block degradation information to the previous accumulated block degradation information in response to a power control signal indicating a power-off, and to determine whether a sensing operation for each of the plurality of pixel blocks is to be performed by comparing the current accumulated block degradation information for each of the plurality of pixel blocks with a sensing reference degradation amount, and a sensing circuit configured to selectively perform the sensing operation for each of the plurality of pixel blocks.

Organic light-emitting diode display device performing a sensing operation, and method of sensing degradation of an organic light-emitting diode display device

A display device may include a timing controller which generates on-clock and off-clock signals, a level shifter which sequentially generates gate clock signals each having a rising edge and a falling edge respectively synchronized with a rising edge of the on-clock signal and a falling edge of the off-clock signal, the gate clock signals having a voltage corresponding to a gate driving voltage, a gate driver generating gate signals based on the gate clock signals, an over-current detector detecting an over-current by sensing a current of each of the gate clock signals at a time point when the falling edge of the on-clock signal is generated in an on-current detection mode, and generates a shutdown signal in response to the detected over-current, and a voltage generator providing the gate driving voltage to the level shifter and stops providing the gate driving voltage in response to the generated shutdown signal.

Display device including level shifter generating gate clock signals synchronized with rising edge and falling edge of clock signal

A display device includes a display panel which displays an image, and a control circuit board connected to the display panel. The control circuit board includes a controller which analyzes the image in real time and determines in real time a digital-type power voltage based on the image, and a voltage generator which generates an analog-type power voltage based on the digital-type power voltage received from the controller. The voltage generator includes a digital-analog converter which converts the digital-type power voltage into the analog-type power voltage and outputs the analog-type power voltage.

Display device having a voltage generator with digital-analog converter for varying output power voltage

A display device includes a display panel including a pixel circuit, a display panel driving circuit that drives the display panel, a voltage generating circuit that receives an input power supply voltage when the display device is powered on and generates display panel voltages and driving circuit voltages based on the input power supply voltage, and an over-current protecting circuit that monitors an over-current generated inside the display device and generates a shut-down request signal when the over-current is detected. The voltage generating circuit outputs an initialization voltage at a first time point corresponding to a time point at which the input power supply voltage is received. The display panel driving circuit outputs a scan clock signal at a second time point. The over-current protecting circuit performs a first over-current protecting operation in a power-on monitoring period set between the first time point and the second time point.

Display device and method of performing an over-current protecting operation thereof

A gamma voltage generator within a display device includes a plurality of gamma generation circuits that respectively generate a plurality of gamma voltages. At least one gamma generation circuit includes an input circuit configured to receive a first reference voltage and a second reference voltage, a reference voltage select circuit configured to select a reference voltage among the first reference voltage and the second reference voltage by comparing a gamma voltage generated by the at least one gamma generation circuit with the first reference voltage and the second reference voltage, a digital-to-analog conversion circuit configured to generate an analog voltage corresponding to a gamma code based on the reference voltage selected by the reference voltage select circuit, and an output circuit configured to output the gamma voltage based on the analog voltage.

Gamma voltage generator, display driver, display device and method of generating a gamma voltage

A display device includes a switch, an initialization line, a capacitor, a data line, a first transistor, a second transistor, a driving transistor, and a diode. The capacitor includes a first electrode and a second electrode. To the first electrode through at least the initialization line, the switch may output a first voltage in a first period of a horizontal time and may output a second voltage unequal to the first voltage in a second period of the horizontal time. The first transistor may connect the data line to the first electrode in response to a scan signal. The driving transistor may provide a driving current based on a voltage of the first electrode. The second transistor may connect the initialization line to the second electrode in response to an initialization signal. The diode may emit light based on the driving current.

Pixel of an organic light emitting diode display device, and organic light emitting diode display device

A gate clock generator of a display device includes a carry clock generator configured to sequentially generate N carry clock signals based on a carry-on clock signal and a carry-off clock signal, a scan clock generator configured to generate N scan clock signals based on a scan-on clock signal and a scan-off clock signal, and a sensing clock generator configured to generate N sensing clock signals based on a sensing-on clock signal and a sensing-off clock signal. In a multi-clock mode of the display device, during an on period of a K-th carry clock signal, the scan clock generator outputs a K-th scan clock signal such that the K-th scan clock signal has a number of pulses that corresponds to a number of pulses of the scan-on clock signal in the on period of the K-th carry clock signal, and the sensing clock generator outputs a K-th sensing clock signal such that the K-th sensing clock signal has a number of pulses that corresponds to a number of pulses of the sensing-on clock signal in the on period of the K-th carry clock signal.

Gate clock generator and display device

A display device includes a display panel including pixels, a data driver providing data signals to the pixels, a scan driver providing scan signals to the pixels, a DC-DC converter converting an input voltage to a power supply voltage and supplying the power supply voltage to the display panel, a feedback circuit having a variable impedance and providing a feedback path of the power supply voltage to the DC-DC converter by receiving the power supply voltage supplied from the DC-DC converter to the display panel and providing an error signal corresponding to a difference between the feedback voltage and a reference voltage to the DC-DC converter, and a controller controlling the data driver and the scan driver, calculating a panel load of the display panel based on input image data, and adjusting the variable impedance of the feedback circuit according to the calculated panel load.

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Hwaseong-si, South Korea

Siduk Sung