POWER SAVING DRIVING CIRCUIT FOR OLED DEVICE OF THE DISPLAYING DEVICE OF PASSIVE MATRIX OLED

摘要

A driving circuit for an OLED of a passive matrix organic EL(Electro-Luminescence) display device is provided to precharge the OLED with a light emitting threshold voltage by using a variable voltage clamping circuit, instead of a zener diode. A driving circuit for an OLED includes a variable voltage clamping circuit(20) and a data driver(30). The variable voltage clamping circuit varies an output voltage and precharges the OLED with a light emitting threshold voltage. The data driver is turned off during a data period and supplies a current from a current source through a data line to the organic EL diode. The data driver includes a precharge switch and a reset switch. The precharge switch is turned on during a precharge period, so that the data line is discharged to a preset precharge voltage by using the variable voltage clamping circuit. The reset switch is turned on in response to a reset pulse and completely discharges the data line.