Semiconductor device

Abstract

The present invention provides a semiconductor device in which a power line is not affected by noise due to a voltage drop caused by instantaneous high-current consumption in the buffer portion and that has no possibility that a logic portion malfunctions. In a case where the same potential is supplied to a logic portion and a buffer portion, by a method in which separate FPC terminals are used for the logic portion and the buffer portion, or by a method in which the FPC terminal is shared but a power line is branched for the logic portion and the buffer portion at a point close to the FPC terminal, a problem that the logic portion is affected by noise generated by a voltage drop of the power line due to instantaneous high-current consumption in the buffer portion can be prevented.

1 . A semiconductor device comprising: 
 a driver circuit including a buffer portion and a logic portion, which is formed over a substrate;    a first connecting terminal over the substrate for supplying a voltage from an external circuit;    a second connecting terminal over the substrate for supplying the voltage from the external circuit;    a first power line connecting the first connecting terminal with the buffer portion electrically; and    a second power line connecting the second connecting terminal with the logic portion electrically.    
   
   
       2 . The semiconductor device according to  claim 1 , 
 wherein a width of the first power line is wider than a width of the second power line.    
   
   
       3 . The semiconductor device according to  claim 1 , 
 wherein the voltage has a ground potential.    
   
   
       4 . The semiconductor device according to  claim 1 , 
 wherein the substrate has an insulating surface.    
   
   
       5 . The semiconductor device according to  claim 1 , further comprising a pixel portion connected to the buffer portion, the pixel portion is formed over the substrate.  
   
   
       6 . The semiconductor device according to  claim 1 , 
 wherein the driver circuit performs a line-sequential driving.    
   
   
       7 . The semiconductor device according to  claim 1 , 
 wherein the logic portion comprises at least one of a latch circuit and a shift register circuit.    
   
   
       8 . The semiconductor device according to  claim 1 , 
 wherein the buffer portion comprises at least one of a level shifter circuit and a buffer circuit.    
   
   
       9 . The semiconductor device according to  claim 1 , 
 wherein the semiconductor device is a display device including a self-luminous element, or a display device including a liquid crystal element.    
   
   
       10 . A semiconductor device comprising: 
 a driver circuit including a buffer portion and a logic portion, which is formed over a substrate;    a connecting terminal over the substrate for supplying a voltage from an external circuit; and    a power line extended from the connecting terminal,    wherein the power line is branched at a point of ⅗or less of a length of the power line from the connecting terminal to the buffer portion, a first branch of the power line is electrically connected to the buffer portion and a second branch of the power line is electrically connected to the logic portion.    
   
   
       11 . The semiconductor device according to  claim 10 , 
 wherein a width of the first branch of the power line is wider than a width of the second branch of the power line.    
   
   
       12 . The semiconductor device according to  claim 10 , 
 wherein the voltage has a ground potential.    
   
   
       13 . The semiconductor device according to  claim 10 , 
 wherein the substrate has an insulating surface.    
   
   
       14 . The semiconductor device according to  claim 10 , further comprising a pixel portion connected to the buffer portion, the pixel portion is formed over the substrate.  
   
   
       15 . The semiconductor device according to  claim 10 , 
 wherein the driver circuit performs a line-sequential driving.    
   
   
       16 . The semiconductor device according to  claim 10 , 
 wherein the logic portion comprises at least one of a latch circuit and a shift register circuit.    
   
   
       17 . The semiconductor device according to  claim 10 , 
 wherein the buffer portion comprises at least one of a level shifter circuit and a buffer circuit.    
   
   
       18 . The semiconductor device according to  claim 10 , 
 wherein the semiconductor device is a display device including a self-luminous element, or a display device including a liquid crystal element.    
   
   
       19 . The semiconductor device according to  claim 10 , 
 wherein the power line is branched at a point of ⅓or less of the length of the power line from the connecting terminal to the buffer portion.    
   
   
       20 . A semiconductor device comprising: 
 a driver circuit including a first circuit and a second circuit, which is formed over a substrate;    a first connecting terminal over the substrate for supplying a voltage from an external circuit;    a second connecting terminal over the substrate for supplying the voltage from the external circuit;    a first power line connecting the first connecting terminal with the first circuit electrically; and    a second power line connecting the second connecting terminal with the second circuit electrically,    wherein the first circuit and the second circuit is connected electrically.    
   
   
       21 . The semiconductor device according to  claim 20 , 
 wherein a width of the first power line is wider than a width of the second power line.    
   
   
       22 . The semiconductor device according to  claim 20 , 
 wherein the voltage has a ground potential.    
   
   
       23 . The semiconductor device according to  claim 20 , 
 wherein the substrate has an insulating surface.    
   
   
       24 . The semiconductor device according to  claim 20 , further comprising a pixel portion connected to the first circuit, the pixel portion is formed over the substrate.  
   
   
       25 . The semiconductor device according to  claim 20 , 
 wherein the driver circuit performs a line-sequential driving.    
   
   
       26 . The semiconductor device according to  claim 20 , 
 wherein the second circuit comprises at least one of a latch circuit and a shift register circuit.    
   
   
       27 . The semiconductor device according to  claim 20 , 
 wherein the first circuit comprises at least one of a level shifter circuit and a buffer circuit.    
   
   
       28 . The semiconductor device according to  claim 20 , 
 wherein the semiconductor device is a display device including a self-luminous element, or a display device including a liquid crystal element.    
   
   
       29 . A semiconductor device comprising: 
 a driver circuit including a first circuit and a second circuit, which is formed over a substrate;    a connecting terminal over the substrate for supplying a voltage from an external circuit; and    a power line extended from the connecting terminal,    wherein the power line is branched at a point of ⅗or less of a length of the power line from the connecting terminal to the first circuit, a first branch of the power line is electrically connected to the first circuit and a second branch of the power line is electrically connected to the second circuit, and    wherein the first circuit and the second circuit is connected electrically.    
   
   
       30 . The semiconductor device according to  claim 29 , 
 wherein a width of the first branch of the power line is wider than a width of the second branch of the power line.    
   
   
       31 . The semiconductor device according to  claim 29 , 
 wherein the voltage has a ground potential.    
   
   
       32 . The semiconductor device according to  claim 29 , 
 wherein the substrate has an insulating surface.    
   
   
       33 . The semiconductor device according to  claim 29 , further comprising a pixel portion connected to the first circuit, the pixel portion is formed over the substrate.  
   
   
       34 . The semiconductor device according to  claim 29 , 
 wherein the driver circuit performs a line-sequential driving.    
   
   
       35 . The semiconductor device according to  claim 29 , 
 wherein the second circuit comprises at least one of a latch circuit and a shift register circuit.    
   
   
       36 . The semiconductor device according to  claim 29 , 
 wherein the first circuit comprises at least one of a level shifter circuit and a buffer circuit.    
   
   
       37 . The semiconductor device according to  claim 29 , 
 wherein the semiconductor device is a display device including a self-luminous element, or a display device including a liquid crystal element.    
   
   
       38 . The semiconductor device according to  claim 29 , 
 wherein the power line is branched at a point of ⅓or less of the length of the power line from the connecting terminal to the first circuit.