# US 8,570,456 B2 · Semiconductor device, display device and electronic device equipped with the semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,570,456 B2 - Document ID: US8570456B2 - Status: Granted - Kind: B2 - Application number: 12/978,802 - Filed: 2010-12-27 - Published: 2011-04-21 - Granted: 2013-10-29 - Earliest claimed: 2005-08-12 - Assignees: Semiconductor Energy Laboratory Co., Ltd. - Applicants: Hajime Kimura - Inventors: Hajime Kimura - Web page: https://patentgrep.com/patent/US8570456B2 ## CPC - G09G 3/325: the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver - G09G 2300/0417: Special arrangements specific to the use of low carrier mobility technology - G09G 2300/0842: forming a memory circuit, e.g. a dynamic memory with one capacitor - G09G 2300/0866: by means of changes in the pixel supply voltage - G09G 2310/0248: Precharge or discharge of column electrodes before or after applying exact column voltages - G09G 2310/0262: The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes - G09G 2310/027: Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters - G09G 2320/0223: Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes - G09G 2320/0252: Improving the response speed - H10K 59/123: Connection of the pixel electrodes to the thin film transistors [TFT] - H10K 59/131: Interconnections, e.g. wiring lines or terminals - H10K 59/80522: {combined with auxiliary electrodes} - H10K 2102/3026: {Top emission} - 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) - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract The present invention provides a semiconductor device which can prevent a current from flowing into a display element at a signal writing operation, without increasing power consumption and without changing a potential of a power supply for supplying a current to a load in each row. When a predetermined current is supplied to a transistor to set a gate-source voltage of the transistor, a potential of a gate terminal of the transistor is adjusted so as to prevent a current from flowing into a load which is connected to a source terminal of the transistor. Thus, a potential of a wire connected to the gate terminal of the transistor is made different from that of a wire connected to a drain terminal of the transistor. At that time, an operation of a transistor is shifted so as to allow a large amount of current to flow, and influences by intersection capacitance parasitic to a wire or the like or wire resistance are hardly caused, and a set operation is conducted quickly. ## Claims ### Claim 1 A display device comprising: a pixel comprising: a first transistor; a second transistor; a switch; a capacitor; and a load; and a driver circuit provided in an IC chip, wherein one of a source and a drain of the first transistor is electrically connected to a first terminal of the switch, wherein the other of the source and the drain of the first transistor is electrically connected to a second terminal of the switch and one of a source and a drain of the second transistor, wherein a gate of the first transistor is electrically connected to a gate of the second transistor and a first terminal of the capacitor, wherein the other of the source and the drain of the second transistor is directly connected to the load, wherein a second terminal of the capacitor is electrically connected to the other of the source and the drain of the second transistor and the load, and wherein the first transistor comprises an oxide semiconductor. ### Claim 2 (depends on 1) The display device according to claim 1 wherein the oxide semiconductor comprises InGaZnO. ### Claim 3 (depends on 1) The display device according to claim 1 wherein the driver circuit comprises a signal line driver circuit. ### Claim 4 (depends on 1) The display device according to claim 1 wherein the display device is incorporated into one selected from the group consisting of a television receiver, a mobile phone, a camera, a computer, a portable image reproducing device, a goggle-type display, and a game machine. ### Claim 5 (depends on 1) The display device according to claim 1, wherein the second transistor comprises the oxide semiconductor. ### Claim 6 (depends on 1) The display device according to claim 1, wherein the load has a rectifying property. ### Claim 7 A display device comprising: a first wire to which a first potential is applied; a second wire to which a second potential is applied; a pixel comprising: a first transistor; a second transistor; a first switch; a second switch; a capacitor; and a load; and a driver circuit provided in an IC chip; wherein one of a source and a drain of the first transistor is electrically connected to a first terminal of the first switch and the first wire, wherein the other of the source and the drain of the first transistor is electrically connected to a second terminal of the first switch and one of a source and a drain of the second transistor, wherein a gate of the first transistor is electrically connected to a gate of the second transistor, a first terminal of the capacitor, and a first terminal of the second switch, wherein a second terminal of the capacitor is electrically connected to the other of the source and the drain of the second transistor and the load, wherein a second terminal of the second switch is electrically connected to the second wire, wherein a value of the first potential is different from that of the second potential, and wherein the first transistor comprises an oxide semiconductor. ### Claim 8 (depends on 7) The display device according to claim 7 wherein the oxide semiconductor comprises InGaZnO. ### Claim 9 (depends on 7) The display device according to claim 7 wherein the driver circuit comprises a signal line driver circuit. ### Claim 10 (depends on 7) The display device according to claim 7 wherein the display device is incorporated into one selected from the group consisting of a television receiver, a mobile phone, a camera, a computer, a portable image reproducing device, a goggle-type display, and a game machine. ### Claim 11 (depends on 7) The display device according to claim 7, wherein the second transistor comprises the oxide semiconductor. ### Claim 12 (depends on 7) The display device according to claim 7, wherein the load has a rectifying property. ### Claim 13 A display device comprising: a first wire to which a first potential is applied; a second wire to which a second potential is applied; a pixel comprising: a first transistor; a second transistor; a first switch; a second switch; a third switch; a current source; a capacitor; and a load; and a driver circuit, wherein one of a source and a drain of the first transistor is electrically connected to a first terminal of the first switch and the first wire, wherein the other of the source and the drain of the first transistor is electrically connected to a second terminal of the first switch and one of a source and a drain of the second transistor, wherein a gate of the first transistor is electrically connected to a gate of the second transistor, a first terminal of the capacitor, and a first terminal of the second switch, wherein a second terminal of the capacitor is electrically connected to the other of the source and the drain of the second transistor, the load, and a first terminal of the third switch, wherein a second terminal of the second switch is electrically connected to the second wire, wherein a second terminal of the third switch is electrically connected to the current source, wherein a value of the first potential is different from that of the second potential, and wherein the first transistor comprises an oxide semiconductor. ### Claim 14 (depends on 13) The display device according to claim 13 wherein the oxide semiconductor comprises InGaZnO. ### Claim 15 (depends on 13) The display device according to claim 13 wherein the driver circuit comprises a signal line driver circuit. ### Claim 16 (depends on 13) The display device according to claim 13 wherein the display device is incorporated into one selected from the group consisting of a television receiver, a mobile phone, a camera, a computer, a portable image reproducing device, a goggle-type display, and a game machine. ### Claim 17 (depends on 13) The display device according to claim 13, wherein the second transistor comprises the oxide semiconductor. ### Claim 18 (depends on 13) The display device according to claim 13, wherein the load has a rectifying property.