OLED display device

Abstract

The invention provides an OLED display device. According to the OLED display device, a 3T1C structure is employed for driving. A source of a first thin-film transistor is connected to a reference voltage; under control on the potential of the reference voltage, a second thin-film transistor works in a saturation region all the time when normal displaying is carried out to ensure continuity of thedisplay grayscales. Meanwhile, a reference voltage metal layer covering all sub pixels is used for replacing reference voltage routing to provide a reference voltage for the source of the first thin-film transistor, so that the influence on the pixel aperture ratio by the reference voltage routing is eliminated.

Description

technical field [0001] The invention relates to the field of display technology, in particular to an OLED display device. Background technique [0002] Organic light emitting diode (Organic Light Emitting Display, OLED) display device has self-illumination, low driving voltage, high luminous efficiency, short response time, high definition and contrast, nearly 180° viewing angle, wide operating temperature range, and can realize flexible display and With many advantages such as large-area full-color display, it is recognized by the industry as a display device with the most potential for development. [0003] The OLED is a current-driven device. When a current flows through the OLED, the OLED emits light, and the brightness of the light is determined by the current flowing through the OLED itself. Most existing integrated circuits (Integrated Circuit, IC) only transmit voltage signals, so the pixel driving circuit of the OLED needs to complete the task of converting the vol...

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Problems solved by technology

The switching switch K1' is controlled by the switching signal Switch', including the first pin K1', the second pin K2' and the third pin K3'; the gate of the first thin film transistor T1' is connected to the scan signal Scan', the drain is connected to the power supply voltage OVDD', the source is electrically connected to the gate of the second thin film transistor T2' and one end of the capacitor C1'; the drain of the second thin film transistor T2' is connected to the power supply voltage OVDD ', the source is electrically connected to the anode of the organic light emitting diode D1'; the cathode of the organic light emitting diode D1' is connected to the common ground voltage OVSS'; the other end of the capacitor C1' is electrically connected to the source of the second thin film transistor T2'; The gate of the three thin film transistor T3' is connected to the sensing control signal Sense', the source is electrically connected to the source of the second thin film transistor T2', and the drain is electrically connected to the first pin K1' of the switch K'; The second pin K2' of the switch K' is electrically connected to the digital-to-analog converter DAC', and the third pin K3' is electrically connected to the analog-to-digital converter ADC'. When the circuit charges the capacitor C1', it ensures organic light emission The diode D1' does not emit light, and the threshold voltage of the organic light emitting diode D1' needs to be limited to about 10V. The OLED device needs to be made into a triple stack device, which limits the number of layers of the OLED device, and when the organic light emitting diode D10 emits light, it is easy to appear the second thin film The difference between the gate-source voltage and the threshold voltage of the transistor T2' is greater than that of the source-drain voltage, so that the second thin film transistor T2' works in the linear region, displaying discontinuous gray scales, and flows through the power supply voltage OVDD' of the OLED device D1' The voltage drop (IRdrop) has a serious impact on

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