Semiconductor device and method of driving the semiconductor device

Patent metadata

Field	Value
Publication number	US-8994622-B2
Application number	US-201313949317-A
Country	US
Kind code	B2
Filing date	Jul 24, 2013
Priority date	Jan 24, 2002
Publication date	Mar 31, 2015
Grant date	Mar 31, 2015

Abstract

Display irregularities in light emitting devices, which develop due to dispersions per pixel in the threshold value of TFTs for supplying electric current to light emitting elements, are obstacles to increasing the image quality of the light emitting devices. An electric potential in which the threshold voltage of a TFT ( 105 ) is either added to or subtracted from the electric potential of a reset signal line ( 110 ) is stored in capacitor means ( 108 ). A voltage, in which the corresponding threshold voltage is added to an image signal, is applied to a gate electrode of a TFT ( 106 ). TFTs within a pixel are disposed adjacently, and dispersion in the characteristics of the TFTs does not easily develop. The threshold value of the TFT ( 105 ) is thus cancelled, even if the threshold values of the TFTs ( 106 ) differ per pixel, and a predetermined drain current can be supplied to an EL element ( 109 ).

First claim

What is claimed is

1. A semiconductor device comprising:
a light-emitting element;
a first transistor;
a second transistor;
a third transistor; and
a capacitor,
wherein one of a source and a drain of the first transistor is electrically connected to the light-emitting element,
wherein a first electrode of the capacitor is directly connected to a gate of the first transistor,
wherein a second electrode of the capacitor is directly connected to one of a source and a dr…

Assignees

• Semiconductor Energy Lab

Inventors

• Kimura Hajime
• Tanada Yoshifumi

Classifications

• G09G3/3648

  Physics · mapped topic

• G09G3/3283

  Physics · mapped topic

• G09G2300/0842

  Physics · mapped topic

• G09G2310/08

  Physics · mapped topic

• G09G3/3275

  Physics · mapped topic