LIGHT EMITTING DEVICE AND DISPLAYING DEVICE, ESPECIALLY SUPPLY A DIGITAL DATA SIGNAL OF A MINIMUM AMPLITUDE TO A DATA LINE IN WHICH THE PARASITIC CAPACITANCE IS MAINTAINED LOW

摘要

PURPOSE: A light emitting device and a displaying device are provided to reduce consumption power by providing a digital data signal having a minimum amplitude to a data line whose parasitic capacitance is suppressed in low. CONSTITUTION: Each pixel of a display device is comprised of an organic EL(ElectroLuminescence) device(40), a driving TFT(Thin Film Transistor)(36), a control TFT(32), and a control capacitance(38). The driving TFT is provided between the organic EL device and an EL power source to control power supply to the organic EL device. The control TFT is coupled between a constant voltage source and the driving TFT. The control TFT receives a digital control signal through a gate and then determines whether maintaining a gate voltage of the driving TFT. A control pulse signal for specifying a light emitting period of the organic EL device is supplied to a control line. The control capacitance is coupled between the control line and the driving TFT. During a light emitting period specified by the control pulse signal, if the control TFT is off-state and a gate voltage(V2) of the driving TFT floats, the gate voltage is shifted toward a voltage depending on the control pulse signal.