# US 2014/0192098 A1 · Semiconductor Device and Driving Method Thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0192098 A1 - Document ID: US20140192098A1 - Status: Published application - Kind: A1 - Application number: 14/155,517 - Filed: 2014-01-15 - Published: 2014-07-10 - Earliest claimed: 2001-10-30 - Assignees: Semiconductor Energy Laboratory Co., Ltd. - Applicants: Semiconductor Energy Laboratory Co., Ltd. - Inventors: Hajime Kimura; Yoshifumi Tanada - Web page: https://patentgrep.com/patent/US20140192098A1 ## CPC - G09G 3/3225: using an active matrix - G09G 3/2022: {using sub-frames} - G09G 3/32: semiconductive, e.g. using light-emitting diodes [LED] - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 3/3266: Details of drivers for scan electrodes - G09G 3/3283: in which the data driver supplies a variable data current for setting the current through, or the voltage across, the light-emitting elements - G09G 3/3291: in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements - G09G 2300/0814: used for selection purposes, e.g. logical AND for partial update - G09G 2300/0819: used for counteracting undesired variations, e.g. feedback or autozeroing - G09G 2300/0842: forming a memory circuit, e.g. a dynamic memory with one capacitor - G09G 2300/0861: with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes - G09G 2300/0866: by means of changes in the pixel supply voltage - G09G 2300/0876: Supplementary capacities in pixels having special driving circuits and electrodes instead of being connected to common electrode or ground; Use of additional capacitively coupled compensation electrodes - G09G 2300/088: using a non-linear two-terminal element - G09G 2310/027: Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters - G09G 2310/0275: Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current - G09G 2310/061: for resetting or blanking - G09G 2320/0233: Improving the luminance or brightness uniformity across the screen - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract Brightness irregularities that develop in a light emitting device due to is persion among pixels in the threshold values of TFTs used for supplying electric current to light emitting devices become obstacles to improved image quality of the light emitting device. As an image signal input to a pixel from a source signal line, a desired electric potential is applied to a gate electrode of a TFT for supplying electric current to an EL device, through a TFT having its gate and drain connected to each other. A voltage equal to the TFT threshold value is produced between the source and the drain of the TFT 105. An electric potential in which the image signal is offset by the amount of the threshold value is therefore applied to the gate electrode of the TFT. Further, TFTs are disposed in close proximity to each other within the pixel, so that dispersions in the TFT characteristics do not easily develop. A desired drain current can thus be supplied to the EL device even if there is dispersion in the threshold values of the TFTs among pixels, because this is offset by the threshold value of the TFT. ## Claims ### Claim 1 (canceled) ### Claim 2 A driving method for a semiconductor device comprising a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor and a light emitting element, wherein one of a source and a drain of the first transistor is electrically connected to one of a source and a drain of the second transistor, wherein a gate of the first transistor is electrically connected to the other of the source and the drain of the second transistor, wherein one of a source and a drain of the third transistor is electrically connected to the one of the source and the drain of the first transistor, wherein the other of the source and the drain of the third transistor is electrically connected to the light emitting element, wherein one of a source and a drain of the fourth transistor is electrically connected to the other of the source and the drain of the first transistor, wherein the other of the source and the drain of the fourth transistor is electrically connected to a first line and wherein one of a source and a drain of the fifth transistor is electrically connected to the other of the source and the drain of the first transistor, the driving method comprising the steps of: supplying an electrical potential of an image signal to the other of the source and the drain of the fifth transistor while the second transistor and the fifth transistor are in an on-state and the third transistor and the fourth transistor are in an off-state; and emitting light from the light emitting element while the second transistor and the fifth transistor are in an off-state and the third transistor and the fourth transistor are in an on-state. ### Claim 3 (depends on 2) The semiconductor device according to claim 2, wherein the first transistor is a P-channel transistor. ### Claim 4 (depends on 2) The driving method according to claim 2, wherein a capacitive means is electrically connected to the gate of the first transistor. ### Claim 5 (depends on 2) The driving method according to claim 2, wherein a source signal line is electrically connected to the other of the source and the drain of the fifth transistor. ### Claim 6 (depends on 2) The driving method according to claim 2, wherein a an electric power source line is electrically connected to the other of the source and the drain of the fourth transistor. ### Claim 7 (depends on 2) The driving method according to claim 2, wherein a first gate signal line is electrically connected to a gate of the second transistor, and wherein a second gate signal line is electrically connected to a gate of the fifth transistor. ### Claim 8 (depends on 2) The driving method according to claim 2, wherein a third gate signal line is electrically connected to a gate of the third transistor, and wherein a fourth gate signal line is electrically connected to a gate of the fourth transistor. ### Claim 9 A driving method for a semiconductor device comprising a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor and a light emitting element, wherein one of a source and a drain of the first transistor is electrically connected to one of a source and a drain of the second transistor, wherein a gate of the first transistor is electrically connected to the other of the source and the drain of the second transistor, wherein one of a source and a drain of the third transistor is electrically connected to the one of the source and the drain of the first transistor, wherein the other of the source and the drain of the third transistor is electrically connected to the light emitting element, wherein one of a source and a drain of the fourth transistor is electrically connected to the other of the source and the drain of the first transistor, wherein the other of the source and the drain of the fourth transistor is electrically connected to a first line and wherein one of a source and a drain of the fifth transistor is electrically connected to the other of the source and the drain of the first transistor, the driving method comprising the steps of: turning on the second transistor; turning on the fifth transistor; turning off the third transistor; turning off the fourth transistor; supplying an electrical potential of an image signal to the other of the source and the drain of the fifth transistor while the second transistor and the fifth transistor are in an on-state and the third transistor and the fourth transistor are in an off-state; turning off the second transistor; turning off the fifth transistor; turning on the third transistor; turning on the fourth transistor; and emitting light from the light emitting element while the second transistor and the fifth transistor are in an off-state and the third transistor and the fourth transistor are in an on-state. ### Claim 10 (depends on 9) The semiconductor device according to claim 9, wherein the first transistor is a P-channel transistor. ### Claim 11 (depends on 9) The driving method according to claim 9, wherein a capacitive means is electrically connected to the gate of the first transistor. ### Claim 12 (depends on 9) The driving method according to claim 9, wherein a source signal line is electrically connected to the other of the source and the drain of the fifth transistor. ### Claim 13 (depends on 9) The driving method according to claim 9, wherein a an electric power source line is electrically connected to the other of the source and the drain of the fourth transistor. ### Claim 14 (depends on 9) The driving method according to claim 9, wherein a first gate signal line is electrically connected to a gate of the second transistor, and wherein a second gate signal line is electrically connected to a gate of the fifth transistor. ### Claim 15 (depends on 9) The driving method according to claim 9, wherein a third gate signal line is electrically connected to a gate of the third transistor, and wherein a fourth gate signal line is electrically connected to a gate of the fourth transistor. ### Claim 16 A driving method for a semiconductor device comprising a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor and a light emitting element, wherein one of a source and a drain of the first transistor is electrically connected to one of a source and a drain of the second transistor, wherein a gate of the first transistor is electrically connected to the other of the source and the drain of the second transistor, wherein one of a source and a drain of the third transistor is electrically connected to the one of the source and the drain of the first transistor, wherein the other of the source and the drain of the third transistor is electrically connected to the light emitting element, wherein one of a source and a drain of the fourth transistor is electrically connected to the other of the source and the drain of the first transistor, wherein the other of the source and the drain of the fourth transistor is electrically connected to a first line and wherein one of a source and a drain of the fifth transistor is electrically connected to the other of the source and the drain of the first transistor, the driving method comprising the steps of: turning on the first transistor in a first period; turning off the first transistor in a second period; and turning on the first transistor in a third period, wherein an electrical potential of an image signal is supplied to the other of the source and the drain of the fifth transistor in the second period while the second transistor and the fifth transistor are in an on-state and the third transistor and the fourth transistor are in an off-state, and wherein an electric current flows in the light emitting element in the third period while the second transistor and the fifth transistor are in an off-state and the third transistor and the fourth transistor are in an on-state. ### Claim 17 (depends on 16) The semiconductor device according to claim 16, wherein the first transistor is a P-channel transistor. ### Claim 18 (depends on 16) The driving method according to claim 16, wherein a capacitive means is electrically connected to the gate of the first transistor. ### Claim 19 (depends on 16) The driving method according to claim 16, wherein a source signal line is electrically connected to the other of the source and the drain of the fifth transistor. ### Claim 20 (depends on 16) The driving method according to claim 16, wherein a an electric power source line is electrically connected to the other of the source and the drain of the fourth transistor. ### Claim 21 (depends on 16) The driving method according to claim 16, wherein a first gate signal line is electrically connected to a gate of the second transistor, and wherein a second gate signal line is electrically connected to a gate of the fifth transistor. ### Claim 22 (depends on 16) The driving method according to claim 16, wherein a third gate signal line is electrically connected to a gate of the third transistor, and wherein a fourth gate signal line is electrically connected to a gate of the fourth transistor. ### Claim 23 (depends on 16) The driving method according to claim 16, wherein the first period is for initialization. ### Claim 24 (depends on 16) The driving method according to claim 16, wherein the electrical potential of the image signal is supplied to the other of the source and the drain of the fifth transistor in the first period while the second transistor, the third transistor and the fifth transistor are in an on-state and the fourth transistor is in an off-state.