Patent ID: 9530353
Filing Date: 2016-12-27
CPC Classification: G09G

Claim Text:
1. An organic electroluminescent display device, comprising: an organic electroluminescent diode receiving a driving voltage and a first ground voltage; a first driving thin film transistor and a second driving thin film transistor for driving a current to the organic electroluminescent diode, the first driving thin film transistor directly connected to the driving voltage and a second switching thin film transistor, and each of the first and the second driving thin film transistors receiving one of the driving voltage and the first ground voltage; a first switching thin film transistor receiving a data voltage and switched by an nth scan signal to output the data voltage; the second switching thin film transistor switched by a current providing signal to switch one of the driving voltage and the first ground voltage to the second driving thin film transistor; a third switching thin film transistor receiving a second ground voltage and switched by a selection signal to output the second ground voltage to an output terminal of the first switching thin film transistor; a fourth switching thin film transistor connected to an output terminal of the second switching thin film transistor, a gate terminal of the first driving thin film transistor, and a gate terminal of the second driving thin film transistor, and switched by the selection signal; a first capacitor connected to the output terminal of the first switching thin film transistor, the gate terminal of the first driving thin film transistor, and the gate terminal of the second driving thin film transistor; a second capacitor connected to a source terminal of the third switching thin film transistor and a drain terminal of the third switching thin film transistor; and an initial voltage at a first level to initialize the first and the second driving thin-film transistors and shifted to a second level for measuring a threshold voltage of the second driving thin-film transistor; a fifth switching thin film transistor for receiving the initial voltage and switched by an initializing signal to output the initial voltage into the gate terminal of the first driving thin film transistor and the gate terminal of the second driving thin film transistor, wherein “n” is a positive integer, wherein a drain terminal of the fifth switching thin film transistor is connected to the second electrode of the first capacitor, a drain terminal of the fourth switching thin film transistor, the gate terminal of the first driving thin film transistor, and the gate terminal of the second driving thin film transistor; and wherein one electrode of the second capacitor is commonly connected to the output terminal of the first switching thin film transistor and the first electrode of the first capacitor, and another electrode of the second capacitor receives the ground voltage.