Patent Publication Number: US-2021185805-A1

Title: Printed wiring board, electronic circuit, determining method of wiring, and program

Description:
TECHNICAL FIELD 
     The present invention relates to a printed wiring board, an electronic circuit, a determining method of wiring, and a program. 
     BACKGROUND ART 
     In general, a printed wiring board is formed by attaching copper foil, which is to be a transmission line, to an insulation layer. The insulation layer is formed by impregnating, with resin, a glass cloth made of fibers woven in both longitudinal and lateral directions. Therefore, the volume ratio of the fiber and the resin in the insulation layer is not even. Due to this, mutually opposing portions of the insulation layer have different permittivity from each other, depending on a position of the transmission line. This difference in permittivity affects a propagation delay of the transmission line formed on the printed wiring board. 
     Because a positive signal line and a negative signal line, which constitute a differential signal line, are located in different positions from each other, the permittivity is different in mutually opposing portions. This difference in permittivity causes a difference in propagation delay (differential skew) between a positive signal line and a negative signal line. 
     A differential signal requires that a positive signal and a negative signal are different in phase from each other by 180 degrees. However, if the differential skew is generated to reduce the phase difference between the positive signal and the negative signal, insertion loss will increase. For this reason, it is desirable not to cause any differential skew between a positive signal line and a negative signal line. 
     From this perspective, a technology to restrain a differential skew has been proposed. 
     For example, Patent Literature 1 (PTL1) discloses a technology to alleviate a differential skew, by setting a line width to be 75% to 95% of an interval between fibers woven in a glass cloth. 
     Patent Literature 2 (PTL2) discloses a technology to alleviate a differential skew by wiring the differential signal line in a form of a sine wave. 
     Patent Literature 3 (PTL3) discloses a technology to alleviate a differential skew by causing an interval between fibers to match with an interval between differential signal lines. 
     CITATION LIST 
     Patent Literature 
     [PTL1] Japanese Laid-Open Patent Application No. 2014-130860 
     [PTL2] Japanese Laid-Open Patent Application No. 2015-050924 
     [PTL3] WO2016/117320 
     SUMMARY OF INVENTION 
     Technical Problem 
     In the technology disclosed in PTL1, a line width is set to be 75% to 95% of an interval between fibers woven in a glass cloth. An interval between fibers is approximately 0.4 mm to 0.7 mm, in general. Therefore, this technology requires a line width of equal to or more than 0.3 mm. Generally, a line width used for a multilayer circuit board is approximately 0.1 mm; therefore, it is difficult to apply this technology, which requires a line width of equal to or more than 0.3 mm, to an actual product. 
     In addition, the technology disclosed in PTL2 arranges the lines in a form of a sine wave, and therefore requires a wider area than the line width. Therefore, it is difficult to wire the differential signal lines using this technology, in an area having a narrow wiring region, such as immediately below a Large Scale Integrated circuit (LSI). For example, it is difficult to wire a differential signal line with a line width of 0.1 mm using this technique, on a Ball Grid Array (BGA) terminal of 1 mm grid. 
     The technology disclosed in PTL3 causes an interval between fibers to match with an interval between differential signal lines. However, as explained above, an interval between fibers is approximately 0.4 mm to 0.7 mm, in general. Therefore, it is difficult to apply such technology in a wiring region, for example immediately below an LSI having a BGA terminal of 1 mm grid. 
     In view of the above situations, an objective of the present invention is to provide a printed wiring board including wiring having a small differential skew applicable to a narrow wiring region, and a manufacturing method thereof. 
     Solution to Problem 
     To achieve the above-described object, a printed wiring board according to the present invention characterized by comprising: an insulation layer configured by a glass cloth in which fiber is woven, and a resin with which the glass cloth is impregnated; 
     first wiring configured by
         a first line extending on an imaginary straight line that is parallel to the fiber woven in the glass cloth,   a second line extending on an imaginary straight line that is parallel to the first line, the second line being separate from the imaginary straight line on which the first line extends, by a distance resulting from adding ½ of an interval of the fiber to an integer multiple equal to 0 or more of the interval of the fiber, and   a third line connecting lines configuring the first line and the second line; and       

     second wiring configuring by
         a fourth line extending on an imaginary straight line that is parallel to the first line,   a fifth line on an imaginary straight line that is parallel to the fourth line, the fifth line being separate from the imaginary straight line on which the fourth line extends, by a distance resulting from adding ½ of an interval of the fiber to an integer multiple equal to 0 or more of the interval of the fiber, and   a sixth line connecting lines configuring the fourth line and the fifth line, wherein       

     a total line length of the first line and a total line length of the second line are equal to each other, 
     a total line length of the fifth line and a total line length of the sixth line are equal to each other, 
     a total line length of the fourth line and the fifth line and a total line length of the first line and the second line are equal to each other, and 
     a line length of the first wiring and a line length of the second wiring are equal to each other. 
     Advantageous Effect of Invention 
     The present invention enables a printed wiring board to include wiring having a small differential skew applicable to a narrow wiring region. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a plan view of a printed wiring board according to a first example embodiment of the present invention. 
         FIG. 2A  is a sectional view taken along II-II of  FIG. 1 , and  FIG. 2B  is a sectional view taken along II′-II′ of  FIG. 1 . Note that hatching is not drawn in the sectional view, so that the figures are easy to view. 
         FIG. 3A  is an enlarged view of the II-II section of  FIG. 1 ,  FIG. 3B ,  FIG. 3C , and  FIG. 3D  are graphs representing a volume ratio of fibers with respect to resin, in the sectional view of  FIG. 3A . 
         FIG. 4  is a block diagram of a processor that executes a program to form a wiring pattern. 
         FIG. 5  is a flowchart of a determining method of a wiring pattern according to the first example embodiment of the present invention. 
         FIG. 6  is a flowchart of a calculation method of wiring of a selected line in  FIG. 5 . 
         FIG. 7  is a diagram for explaining a calculation method of a wiring pattern in a selected line. 
         FIG. 8  is a plan view of a printed wiring board according to a second example embodiment of the present invention. 
         FIG. 9  is a plan view of a printed wiring board according to a third example embodiment of the present invention. 
         FIG. 10  is a plan view of a printed wiring board according to a fourth example embodiment of the present invention. 
         FIG. 11  is a plan view of a printed wiring board according to a fifth example embodiment of the present invention. 
         FIG. 12  is a plan view of a printed wiring board according to a sixth example embodiment of the present invention. 
         FIG. 13  is a plan view of a printed wiring board according to a seventh example embodiment of the present invention. 
         FIG. 14  is a diagram for explaining a printed wiring board according to a modification example. 
         FIG. 15  is a plan view of a printed wiring board according to an exemplary embodiment of the present invention. 
     
    
    
     EXAMPLE EMBODIMENT 
     The following describes a printed wiring board and a manufacturing method thereof according to example embodiments of the present invention, with reference to the drawings. 
     First Example Embodiment 
     As illustrated in  FIG. 1  and  FIGS. 2A and 2B , a printed wiring board  110  according to the first example embodiment is configured by: insulation layers  25  and  26 , formed by impregnating, with a resin  23 , a glass cloth  22  made of fibers  20 ,  21  woven in both longitudinal and lateral directions; and copper foil and the like being a conductor, and is configured by a transmission line  12  wired between the insulation layers  25  and  26 ; and a ground layer  24  sandwiching the insulation layers  25  and  26 . An interval of fibers  20  is set to be Pg 1 . As follows, the interval of fibers  20  is referred to as a glass cloth interval. 
     As illustrated in  FIGS. 2A and 2B , the fibers  20  configuring the insulation layers  25  and  26  are disposed parallel to each other. 
     As illustrated in  FIG. 1 , the transmission line  12  is configured by a positive signal line  10  and a negative signal line  11 . Each of the positive signal line  10  and the negative signal line  11  is formed to have a line width of 0.1 to 0.2 mm. The positive signal line  10  and the negative signal line  11  are lines having an interval Dp therebetween and being parallel to each other. The relationship: the interval Dp&lt;the glass cloth interval Pg 1  is satisfied. 
     The transmission line  12  is a winding line being repeatedly curved. The positive signal line  10  has: a line of a length L 2i−1  at a positive signal line section S 1   2i−1  which is a straight portion parallel to the fiber  20 ; and a line of a line length L 2i  at a positive signal line section S 1   2i . The negative signal line  11  has: a line of a length L′ 2i−1  at a negative signal line section S 1 ′ 2i−1  which is a straight portion parallel to the positive signal line section S 1   2i−1 ; and a length of L′ 2i  at a negative signal line section S 1 ′ 2i . Note that “i” denotes arbitrary natural number. Note that the positive signal line section S 1   2i−1  and the negative signal line section S 1 ′ 2i−1  each represent an odd-number line section, whereas the positive signal line section S 1   2i  and the negative signal line section S 1 ′ 2i  each represent an even-numbered line section. 
     A straight line connects between the positive signal line section S 1   2i−1  and the positive signal line section S 1   2i . Similarly, a straight line connects between the negative signal line section S 1 ′ 2i−1  and the negative signal line section S 1 ′ 2i . 
     The odd-numbered positive signal line section S 1   2i−1  extends along a same imaginary straight line, whereas the even-numbered positive signal line section S 1   2i  extends along a same imaginary straight line that is parallel to the positive signal line sections S 1   2i−1 . Similarly, the odd-numbered negative signal line section S 1 ′ 2i−1  extends along a same imaginary straight line, whereas the even-numbered negative signal line section S 1 ′ 2i  extends along a same imaginary straight line that is parallel to the negative signal line section S 1 ′ 2i−1 . An interval between the imaginary straight line along which the positive signal line section S 1   2i−1  extends and the imaginary straight line along which the positive signal line section S 1   2i  extends is ½ of the glass cloth interval Pg 1 . Similarly, the imaginary straight line along which the negative signal line section S 1 ′ 2i−1  extends and the imaginary straight line along which the negative signal line section S 1 ′ 2i  extends is Pg 1 /2. 
     As expressed in Equation 1, a total line length of the positive signal line sections S 1   2i−1  and a total line length of the positive signal line sections S 1   2i  are equal to each other. In addition, a total line length of the negative signal line sections S 1 ′ 2i−1  and a total line length of the negative signal line sections S 1 ′ 2i  are equal to each other. A total line length of the positive signal line section, that is, a total line length of the positive signal line section S 1   2i−1  and the positive signal line section S 1   2i  is equal to a total line length of the negative signal line sections, that is, a total line length of the negative signal line section S 1 ′ 2i−1  and the negative signal line section S 1 ′ 2i . Note that, in Equation 1, “N 1 ” represents the number of the positive signal line sections S 1   2i−1 , “N 2 ” represents the number of the positive signal line section S 1   2i , “N′ 1 ” represents the number of the negative signal line section S 1 ′ 2i−1 , and “N′ 2 ” represents the number of the negative signal line section S 1 ′ 2i , and N=N 1 +N 2i  N′=N′ 1 +N′ 2 . 
     
       
         
           
             
               
                 
                   
                     
                       
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     In addition, an overall length of the positive signal line  10  and an overall length of the negative signal line  11  are equal to each other. 
     The following explains properties of the printed wiring board  110  having the above-described configuration. 
     As illustrated in  FIG. 2A , in the positive signal line section S 1   2i−1  of the positive signal line  10 , a volume ratio of the fibers  20  with respect to the resin  23  is high in a vicinity of the positive signal line  10   a  (opposing regions). On the other hand, as illustrated in  FIG. 2B , in the positive signal line section S 1   2i , a volume ratio of the fibers  20  with respect to the resin  23  is low in a vicinity of the positive signal line  10   b  (opposing regions). 
     Here, both the positive signal line section S 1   2i−1  and the positive signal line section S 1   2i  extend along an imaginary straight line that is parallel to the fiber  20 . Therefore, in a vicinity of the positive signal line sections S 1   1  to S 2·N1−1  (opposing regions), volume ratios of the fibers  20  with respect to the resin  23  per unit distance are substantially equal to each other. Therefore, permittivity between each positive signal line section S 1   1 , S 1   j , . . . , S 2·N1−1  and the ground layer  24  per unit distance is substantially equal to each other. Similarly, permittivity between each positive signal line section S 1   2i  S 1   4 , . . . , S 2·N2  and the ground layer  24  per unit distance is substantially equal to each other. 
     Here, as illustrated in  FIG. 3A , the fiber  20  is thickest at the center position of the fiber, and thinner towards outside. Therefore, as illustrated in  FIGS. 3B, 3C, and 3D , a volume ratio of the fiber  20  with respect to the resin  23  is in a form like a mountain that is laterally symmetrical, with its vertex being the center position of the fiber. In addition, the fiber  20  is woven at a glass cloth interval Pg 1 . Therefore, a volume ratio of the fiber  20  with respect to the resin  23  in a direction perpendicular to the direction of the fiber  20  is repeated in the glass cloth interval Pg 1 . Therefore, as illustrated in  FIG. 3B , at positions  32   a  and  32   b  which are separate from a position  31  at which a volume ratio of the fiber  20  with respect to the resin  23  is high, by Pg 1 /2 in a direction perpendicular to a direction to the fiber  20 , a volume ratio of the fiber  20  with respect to the resin  23  is low. As illustrated in  FIG. 3C , at positions  34   a  and  34   b  which are separate by Pg 1 /2 from a position  33  at which a volume ratio of the fiber  20  with respect to the resin  23  is medium, a volume ratio of the fiber  20  with respect to the resin  23  is also medium. As illustrated in  FIG. 3D , at positions  36   a  and  36   b  which are separate by Pg 1 /2 from a position  35  at which a volume ratio of the fiber  20  with respect to the resin  23  is low, a volume ratio of the fiber  20  with respect to the resin  23  is high. That is, at a position separate by Pg 1 /2 from positions at which a volume ratio of the fiber  20  with respect to the resin  23  is high, a volume ratio of the fiber  20  is low; whereas at a position separate by Pg 1 /2 from positions at which a volume ratio of the fiber  20  with respect to the resin  23  is low, a volume ratio of the fiber  20  is high. 
     Permittivity is higher as a volume ratio of the fiber  20  is higher. Therefore, as permittivity is higher between the odd-numbered positive signal line section S 1   2i−1  and the ground layer  24 , permittivity is lower between the even-numbered positive signal line section S 1   2i  and the ground layer  24 . As permittivity is higher, the propagation delay is larger. Therefore, as a propagation delay for unit distance is larger in the odd-numbered positive signal line section S 1   2i−1 , a propagation delay for unit distance is smaller in the even-numbered positive signal line section S 1   2i . 
     Here, because a total line length of the positive signal line section S 1   2i−1  and a total line length of the positive signal line section S 1   2i  are equal to each other, a propagation delay for the entire positive signal line  10  is equalized. Therefore, a possible range of a propagation delay for unit distance for the entire positive signal line  10  is smaller than a possible range of a propagation delay for unit distance for when the positive signal line is wired freely. 
     On the other hand, the negative signal line sections S 1 ′ 2i−1 , and the negative signal line sections S 1 ′ 2i  are respectively extend along an imaginary straight line that is parallel to the fiber  20 . Therefore, a volume ratio of the fiber  20  with respect to the resin  23  for unit distance in a vicinity of each negative signal line section S 1 ′ 2i−1  is substantially equal. Consequently, permittivity between the negative signal line section S 1 ′ 2i−1  and the ground layer  24  for unit distance is substantially equal to each other. Similarly, permittivity per distance between each negative signal line section S 1 ′ 2i  and the ground layer  24  is substantially equal to one another. 
     Similarly to the positive signal line sections S 1   2i−1 , S 1   2i , as a propagation delay for unit distance is larger in the odd-numbered negative signal line section S 1 ′ 2i−1 , a propagation delay for unit distance is smaller in the even-numbered negative signal line section S 1 ′ 2i . 
     Because a total line length of the negative signal line section S 1 ′ 2i−1  and a total line length of the negative signal line section S 1 ′ 2i  are equal to each other, a propagation delay for the entire negative signal line  11  is equalized. Therefore, a possible range of a propagation delay for unit distance for the entire negative signal line  11  is smaller than a possible range of a propagation delay for unit distance when the negative signal line is wired freely. 
     In addition, because the positive signal line  10  and the negative signal line  11  are lines configuring the transmission line  12  sandwiched between the insulation layers  25  and  26 , the possible range of a propagation delay for unit distance is equal between the positive signal line  10  and the negative signal line  11 . 
     Furthermore, because a total line length of the positive signal line sections S 1   2i−1 , S 1   2i  and a total line length of the negative signal line sections S 1 ′ 2i−1 , S 1 ′ 2i  are equal to each other, the maximum value of a differential skew in the transmission line  12  is smaller than the maximum value of a differential skew when the positive signal line  10  and the negative signal line  11  are wired freely. As a result, an effect that a difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  has on a propagation delay is smaller than in case where the positive signal line  10  and the negative signal line  11  are wired freely. 
     In the printed wiring board  110 , a signal generator, which transmits a differential signal, is connected to an end of the transmission line  12 ; and such a component as a semiconductor integrated circuit, which receives a differential signal, is connected to the other end, for use. 
     A voltage having a sine wave is applied by the signal generator to the transmission line  12 . Here, a phase difference between voltages applied to the positive signal line  10  and the negative signal line  11  by the signal generator is 180 degrees. 
     In this configuration, as described above, an effect that a difference in permittivity between the resin  23  and the fiber  20  has on a propagation delay is small, due to the property of the printed wiring board  110 . Therefore, an effect of an insertion loss on the transmission line  12  from the signal generator to the component is also small, and therefore, the semiconductor integrated circuit can be operated normally. 
     (Manufacturing Method of Printed Wiring Board) 
     The following explains a manufacturing method of a printed wiring board  110  having the above-described configuration. 
     A glass cloth  22  is prepared by weaving fibers  20  and  21  at a certain pitch. 
     The glass cloth  22  is impregnated with a resin  23 , thereby manufacturing insulation layers  25  and  26 . The resin  23  is composed of an insulating material, such as an epoxy resin, a polyimide resin, or polyester resin, for example. 
     Next, a wiring pattern of the printed wiring board  110  is determined. In accordance with the determined wiring pattern, a transmission line  12  is formed by metal foil, such as copper foil, of a conductor on one surface of the insulation layer  25 . In a forming process of the transmission line  12 , various types of method of forming wiring patterns may be adopted, such as a subtractive process and an additive process. Finally, on the surface of the insulation layer  25 , on which the transmission line  12  is formed, the insulation layer  26  is overlapped, and a pair of ground layers  24 , made of metal foil such as copper foil, is placed in such a manner to sandwich the insulation layer  25 ,  26 , and pressed, thereby manufacturing the printed wiring board  110 . 
     Determination of the wiring pattern may be conducted by executing a computer program. The following explains a determining method of a wiring pattern with reference to the drawings. 
     As illustrated in  FIG. 4 , a processor  200  operable to execute a computer program is configured by: an operating unit  201  such as a keyboard and a mouse; a controller  202  that processes a program, a main storage unit  203  that accumulates data used in executing a program; an auxiliary storage unit  204  that accumulates data such as a program; and a display  205  that displays a result of a program, and the like. 
     The operating unit  201  transmits data input from the keyboard, the mouse, or the like, to the controller  202 . 
     The controller  202  is configured by a Central Processing Unit (CPU), and the like, and executes a program by using data received from the operating unit  201 , the main storage unit  203 , or the auxiliary storage unit  204 . In addition, the controller  202 , where necessary, transmits data during program execution, to the main storage unit  203  or the auxiliary storage unit  204 . During execution of a program, the controller  202  also requests data from the main storage unit  203  or the auxiliary storage unit  204 , where necessary. 
     The main storage unit  203  accumulates data received from the controller  202 . In addition, the main storage unit  203  transmits the accumulated data upon request by the controller  202 . 
     The auxiliary storage unit  204  accumulates data received from the controller  202 . In addition, the auxiliary storage unit  204  transmits the accumulated data such as a program, upon request by the controller  202 . 
     The display  205  receives data from the controller  202 , and displays the data. 
     In a determining method of a wiring pattern, first, a size of a targeted printed wiring board  110 , intervals Pg 1  and Pg 2  of the fibers  20  and  21  of the insulation layers  25  and  26 , and a direction of the fiber  20  are received from the operating unit  201  (S 10 ), as illustrated in  FIG. 5 . Next, in accordance with the size of the printed wiring board  110  which has been received, the controller  202  displays, on the display  205 , a region for the printed wiring board  110  (S 20 ). In accordance with the region for the printed wiring board  110  displayed on the display  205 , a provisional position for the components to be mounted, and a rough wiring pattern are received from the operating unit  201  (S 30 ). Subsequently, the operating unit  201  selects a differential signal line from the rough wiring pattern (S 40 ). 
     The controller  202  extracts a line parallel to the fiber  20  woven into the glass cloth, from the selected differential signal line, and displays the extracted line on the display  205  (S 50 ). Note that a partial section of the line corresponds to this, the corresponding section is extracted as the line. 
     Next, a designer selects a line to which the wiring according to this example embodiment is to be applied, from the lines displayed on the display  205 , and designates the selected line through the operating unit  201  (S 60 ). The controller  202  calculates the wiring of the selected line, using in a later-explained method, and displays the calculated wiring on the display  205  (S 70 ). Whether all the lines to which the wiring method according to the present example embodiment is applied are selected is confirmed on the display  205  (S 80 ). If there is any line left unselected, selection of a line from the extracted lines is conducted again, the selected line is input through the operating unit  201 , and the wiring is determined (S 60 , S 70 ). If there is no line left unselected, the lines for which the wiring pattern is not determined and the positioning of the components are input through the operating unit  201  (S 90 ). In this way, the entire wiring pattern is determined. 
     The following describes details of a method to calculate (S 70 ) wiring with respect to the selected line, with reference to  FIG. 6 . 
     First, an interval Dp between the positive signal line and the negative signal line, and the maximum value L max  of the line length L 2i−1  of the positive signal line section S 1   2i−1  are input through the operating unit  20  (S 700 ). 
     Next, through the operating unit  201 , an angle θ formed between the line  10   c  connecting the positive signal line section S 1   2i−1  and the positive signal line section S 1   2i , and the imaginary straight line to position the positive signal line section S 1   2i−1  are received (S 701 ). Note that 0°&lt;θ&lt;90° holds, as illustrated in  FIG. 7 . 
     Because an interval between the imaginary straight lines to position the positive signal line section S 1   2i−1  and the positive signal line section S 1   2i  are Pg 1 /2, the controller  202  calculates a line length  1  of the line  10   c  and a length dl of a component of the line  10   c  in a direction of the positive signal line section S 1   2i−1 , based on the input angle θ and from Equation 2 (S 702 ). 
     
       
         
           
             
               
                 
                   
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     The controller  202  calculates the line length L 2i−1  of the positive signal line section S 1   2i−1 , the line length L 2i  of the positive signal line section S 1   2i , and the number N of the positive signal line section S 1   i , so as to satisfy Equation 3, based on the length dl of the component of the line  10   c  in the direction of the positive signal line section S 1   2i−1  having been calculated (S 703 ). Here, as illustrated in Equation 3, line lengths L 2i−1 , L 2i  of the positive signal line sections S 1   2i−1  and S 1   2i  are assumed to be equal, in the calculation. Note that L an  represents a length of a selected line. 
     
       
         
           
             
               
                 
                   
                     
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     Next, the controller  202  calculates a positive signal line section S 1   1  of a line length L 1 , which is parallel to the fiber  20 . Here, as illustrated in  FIG. 7 , the positive signal line section S 1   1  is a line whose one end  37   a  is positioned at one end of the selected line, and the other end  37   b  thereof is positioned on the other end of the selected line. Next, a line  10   c  is calculated, whose one end is one end  37   b  of the positive signal line section S 1   1 , and which forms an angle 180°−θ with the positive signal line section S 1   1 , and has a length  1 . Subsequently, the positive signal line section S 1   2  is calculated, whose one end is one end  38   a  of the connected line  10   c , and which is parallel to the positive signal line section S 1   1  and has a line length L 2 . Here, an angle between the positive signal line section S 1   2  and the line  10   c  is 180°−θ. A line  10   d  of a length  1 , whose one end is the other end  38   b  of the positive signal line section S 1   2i  and which forms an angle 180°−θ with the positive signal line section S 1   2  is calculated. Here, the other end  39   a  of the line  10   d  positions on the imaginary straight line that is extended from the positive signal line section S 1   1 . Subsequently, a positive signal line section S 1   j  of a line length L 3 , whose one end is one end  39   a  of the line  10   d , and which is parallel to the positive signal line section S 1   1  is calculated. This process is repeated till reaching the positive signal section S 1   N , thereby calculating wiring for the positive signal line  10  (S 704 ). 
     The controller  202  calculates wiring for the negative signal line  11 , which is shifted towards a direction perpendicular from the direction of the transmission line by an interval Dp between the positive signal line  10  and the negative signal line  11 , from the positive signal line  10  for which the wiring has been determined (S 705 ). 
     Finally, the controller  202  displays the calculated positive signal line  10  and the negative signal line  11 , on the display  205  (S 706 ). 
     In the wiring calculated in the above-described method, the negative signal line  11  is a line which results from moving the positive signal line  10  parallelly. Therefore, the wiring satisfies Equation 4, and an overall length of the positive signal line  10  and an overall length of the negative signal line  11  are equal to each other. Consequently, this will be a configuration of the printed wiring board  110 . 
     
       
         
           
             
               
                 
                   
                     
                       
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     Second Example Embodiment 
     The first example embodiment is an example in which the wiring region has no limitation to be located. However, the invention according to the present application can be applied to such wiring positioned in a narrow wiring region immediately below the LSI having a BGA terminal or the like. The following explains the second example embodiment in which the invention according to the present invention is applied to the wiring positioned in a narrow wiring region. 
     As illustrated in  FIG. 8 , the transmission line  12  of the printed wiring board  120  according to the second example embodiment is formed by a winding line in which winding is repeated up until the BGA terminal, as in the first example embodiment. 
     In  FIG. 8 , the positive signal line section S 1   N  passes between through holes  42  of the BGA terminal, and extends along an imaginary straight line that is parallel to the fiber  20  of the glass cloth. One end of the positive signal line section S 1   N  and a signal through hole  40  of the BGA terminal (or the terminal itself) are connected to each other in a straight line. The line length L N  of the positive signal line section S 1   N  is a length that reaches the positive signal line section S 1   N−1  described later. The positive signal line section S 1   N−1  is in a position separate from a narrow region immediately below the LSI, separate by ½ of the glass cloth interval Pg 1  from the imaginary straight line on which the positive signal line section S 1   N  extends, and extends along the imaginary straight line that is parallel to the positive signal line section S 1   N . The positive signal line section S 1   N  and the positive signal line section S 1   N−1  are connected to each other by a straight line. 
     Similarly, the negative signal line section S 1 ′ N′  passes between the through holes  42  of the BGA terminal, and extends along an imaginary straight line that is parallel to the positive signal line section S 1   N′ . One end of the negative signal line section S 1 ′ N′  and a signal through hole  41  are connected by a straight line. The line length L′ N′  of the negative signal line section is a length that reaches the negative signal line section S 1 ′ N′−1 . The negative signal line section is in a position separate from a narrow region immediately below the LSI, separate by Pg 1 /2 from the imaginary straight line on which the negative signal line section S 1 ′ N′  extends, and extends along the imaginary straight line that is parallel to the negative signal line section S 1 ′ N′ . 
     The positive signal line  10  and the negative signal line  11  respectively extend along an imaginary straight line separate by ½ of the glass cloth interval Pg 1  in the odd-numbered line section and the even-numbered line section. A total line length of the positive signal line section S 1   2i−1  and a total line length of the positive signal line section S 1   2i  are equal to each other, and a total line length of the negative signal line section S 1 ′ 2i−1  and a total line length of the negative signal line section S 1 ′ 2i  are equal to each other. Furthermore, a total line length of the positive signal line sections S 1   2i−1  and S 1   2i  of the positive signal line  10  and are a total line length of the negative signal line sections S 1 ′ 2i−1  and S 1 ′ 2i  of the negative signal line  11  are equal to each other. For this reason, an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 . 
     According to a configuration in this second example embodiment, the transmission line  12  can be wired as a straight line, between the through holes of the BGA terminal. For this reason, even in a BGA terminal of 1 mm grid, which makes the wiring region of 0.3 mm, the positive signal line and the negative signal line of a wiring width of 1 mm can be wired. 
     Third Example Embodiment 
     In examples of the first and second example embodiments, the invention according to the present application is applied to the entire transmission line. However, the invention according to the present applicant may be applied to a partial section of the transmission line, and a conventional technology may be applied to the remaining sections. The following explains a third example embodiment in which the invention according to the present application is applied to a partial section of the transmission line. 
     As illustrated in  FIG. 9 , the printed wiring board  130  according to an example embodiment of the present invention is wiring to which a conventional technology is applied to a wiring section S 1  that is separate from a region immediately below the LSI. 
     In a wiring section  50  in a vicinity of the region immediately below the LSI, a positive signal line section S 1   a  passes between through holes  42 , and extends along an imaginary straight line that is parallel to the fiber  20  of the glass cloth. One end of the positive signal line section S 1   a  and a signal through hole  40  of the BGA terminal are connected to each other in a straight line. The line length L a  of the positive signal line section S 1   a  is a length that reaches the positive signal line section S 1   b  described later. The positive signal line section S 1   b  is in a position separate from a narrow region immediately below the LSI, separate by ½ of the glass cloth interval Pg 1  from the imaginary straight line on which the positive signal line section S 1   a  extends, and extends along the imaginary straight line that is parallel to the positive signal line section S 1   a . The positive signal line section S 1   a  and the positive signal section S 1   b  are connected to each other by a straight line. The positive signal line section S 1   b  and the positive signal line  10  of the wiring section S 1  are also connected to each other by a line. 
     Similarly, the negative signal line section S 1 ′ a  passes between the through holes  42 , and extends along an imaginary straight line that is parallel to the positive signal line section S 1 ′ a . One end of the negative signal line section S 1 ′ a′  and a signal through hole  41  are connected by a straight line. The line length L′ a  of the negative signal line section S 1 ′ a  is a length that reaches the negative signal line section S 1 ′ b . The negative signal line section S 1 ′ b  is in a position separate from a narrow region immediately below the LSI, separate by Pg 1 /2 from the imaginary straight line on which the negative signal line section S 1 ′ a  extends, and extends along the imaginary straight line that is parallel to the negative signal line section S 1 ′ a . The negative signal line section S 1 ′ b  and the negative signal line  11  of the wiring section S 1  are also connected to each other by a line. 
     The line length L a  and the line length L b  of the positive signal line  10  are equal to each other. Similarly, the line length L′ a  and the line length L′ b  of the negative signal line  11  are equal to each other. In addition, a total line length L a +L b  of the positive signal line section S 1   a  and the positive signal line section S 1   b  is equal to a total line length L′ a +L′ b  of the negative signal line section S 1 ′ a  and the negative signal line section S 1 ′ b . Furthermore, an overall length of the positive signal line and an overall length of the negative signal line of the wiring section  50  are equal to each other. 
     The positive signal line section S 1   a  and the positive signal line section S 1   b  respectively extend along an imaginary straight line separate by ½ of the glass cloth interval Pg 1 ; whereas the negative signal line section S 1 ′ a  and the negative signal line section S 1 ′ b  extend along an imaginary straight line separate by ½ of Pg 1 . For this reason, within the section  50 , an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 . 
     In addition, the transmission line  12  in wiring section S 1  is subject to a smaller differential skew than in conventional technologies. Therefore, in the entire wiring sections  50  and  51 , an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small. 
     Fourth Example Embodiment 
     In examples of the first to third example embodiments, the interval between the imaginary straight line on which the odd-numbered positive signal line section S 1   2i−1  extends and the imaginary straight line on which the even-numbered positive signal line section S 1   2i  extends is Pg 1 /2; however, the interval may be Pg 1 (n+½), where “n” is a natural number. 
     As illustrated in  FIG. 10 , on a printed wiring board  140  according to fourth example embodiment of the present invention, a distance between an imaginary straight line on which an odd-numbered positive signal line section S 1   2i−1  extends and an imaginary straight line on which an even-numbered positive signal line section S 1   2i  extends is Pg 1 (n+½). Similarly, a distance between an imaginary straight line on which an odd-numbered negative signal line section S 1 ′ 2i−1  extends and an imaginary straight line on which an even-numbered negative signal line section S 1 ′ 2 , extends is Pg 1 (n+½). 
     The positive signal line section S 1   2i−1  and the positive signal line section S 1   2i  extend along imaginary straight lines separate from each other by Pg 1 (n+½); and the negative signal line section S 1 ′ 2i−1  and the negative signal line section S 1   2i  extend along imaginary straight lines separate from each other by Pg 1 (n+½). 
     Here, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 , the volume ratio of the fiber  20  with respect to the resin  23  is substantially the same, between at a position separate by Pg 1 /2 which is ½ of the period, and at a position separate by Pg 1 (n+½) which results from adding Pg 1 /2 (½ of the period) to “n” multiple of Pg 1  (natural number multiple of the period). 
     For this reason, an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small. 
     Fifth Example Embodiment 
     In examples of the first to fourth example embodiments, the odd-numbered positive signal line section S 1   2i−1  and the even-numbered positive signal line section S 1   2i  are respectively on a same imaginary straight line. However, an example is also possible in which the positive signal line section S 1   2i−1  extends along a plurality of parallel imaginary straight lines with a glass cloth interval Pg 1 , and the positive signal line section S 1   2i  may extends along a plurality of imaginary straight lines, which are separate from the imaginary straight lines on which the positive signal line section S 1   2i−1  extends by Pg 1 (n 2i +½) and parallel to the positive signal line section S 1   2i−1 . That is, the imaginary straight lines along which the positive signal line section S 1   2i  extends are also a plurality of parallel imaginary straight lines aligned with an interval Pg 1 . Here, “n 2i ” is an integer equal to or more than 0, corresponding to the even-numbered section S 1   2i . 
     As illustrated in  FIG. 11 , on the printed wiring board  150  according to fifth example embodiment of the present invention, an interval between the imaginary straight line on which the odd-numbered positive signal line section S 1   2i−1  extends and the imaginary straight line on which the positive signal line section S 1   2i+1  extends is a glass cloth interval Pg 1 . 
     On the other hand, a distance between the imaginary straight line along which the even-numbered positive signal line section S 1   2i  extends and the imaginary straight line along which the odd-numbered positive signal line section S 1   2i−1  extends is Pg 1 /2. A distance between the imaginary straight line on which the positive signal line section S 1   2i +2 extends and the imaginary straight line on which the positive signal line section S 1   2i−1  extends is Pg 1 (1+½). 
     Similarly, on the negative signal line  11 , too, a distance between the imaginary straight line along which the odd-numbered negative signal line section S 1 ′ 2i−1  extends and the imaginary straight line along which the negative signal line section S 1 ′ 2i+1  extends is Pg 1 . 
     On the other hand, a distance between the imaginary straight line along which the even-numbered negative signal line section S 1 ′ 2i  extends and the imaginary straight line along which the odd-numbered negative signal line section S 1 ′ 2i−1  extends is Pg 1 /2. A distance between the imaginary straight line along which the negative signal line section S 1 ′ 2i+2  extends and the imaginary straight line along which the negative signal line section S 1 ′ 2i−1  extends is Pg 1 (1+½). 
     Here, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 , the volume ratios of the fiber  20  with respect to the resin  23  are substantially equal to each other, at two positions separate by an integer multiple of 0 or more of its period, i.e. Pg 1 . In addition, the volume ratios of the fiber  20  with respect to the resin  23  are substantially equal to each other, between at a position separate by ½ of the period, which is Pg 1 /2, and at a position separate by a distance resulting from adding ½ of the period to n 2i -multiple of the distance Pg 1  (the period), which is Pg 1 (n 2i +½). 
     For this reason, an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 . 
     Sixth Example Embodiment 
     In an example of the fifth example embodiment, the even-numbered positive signal line section extends along mutually parallel imaginary straight lines aligned with an interval of Pg 1  therebetween; and the odd-numbered positive signal line section extends along imaginary straight lines between these imaginary straight lines. However, the even-numbered positive signal line section and the odd-numbered positive signal line section do not have to on alternating imaginary straight lines. 
     As illustrated in  FIG. 12 , on the printed wiring board  160  according to the sixth example embodiment of the present invention, a distance between an imaginary straight line on which the positive signal line section S 1   j  extends and an imaginary straight line on which the positive signal line section S 1   j+1  extends is a glass cloth interval Pg 1 . Note that “j” is an order of the positive signal lines sections extending on mutually parallel imaginary straight lines, with an interval Pg 1  therebetween. 
     A distance between an imaginary straight line on which the positive signal line section S 1   j  extends and an imaginary straight line on which the positive signal line section S 1   k  extends is Pg 1 /2. A distance between an imaginary straight line on which the positive signal line section S 1   j  extends and an imaginary straight line on which the positive signal line section S 1   k+1  extends is Pg 1 (1+½). Note that “k” is an order of the positive signal line section which is separate by Pg 1 (n k +½) from the imaginary straight line on which the positive signal line section S 1   j  extends, and is parallel to the positive signal line section S 1   j  extending along the imaginary straight line that is parallel to the positive signal line section S 1   j . “n k ” is an integer equal to or more than 0, in accordance with the section S 1   k . 
     Similarly, a distance between an imaginary straight line on which the negative signal line section S 1 ′ j  extends and an imaginary straight line on which the negative signal line section S 1 ′ j+1  extends is Pg 1 . 
     A distance between an imaginary straight line on which the negative signal line section S 1 ′ j  extends and an imaginary straight line on which the negative signal line section S 1 ′ k  extends is Pg 1 /2. A distance between an imaginary straight line on which the negative signal line section S 1 ′ j  extends and an imaginary straight line on which the negative signal line section S 1 ′ k+1  extends is Pg 1 (1+½). 
     In addition, a total line length of the positive signal line section S 1   j  and a total line length of the positive signal line section S 1   k  are equal to each other. A total line length of the negative signal line section S 1 ′ j  and a total line length of the negative signal line section S 1 ′ k  are equal to each other. A total line length of the positive signal line sections S 1   j  and S 1   k  and a total line length of the negative signal line sections S 1 ′ j  and S 1 ′ k  are equal to each other. Moreover, an overall length of the positive signal line  10  and an overall length of the negative signal line  11  are equal to each other. 
     Here, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 , the volume ratios of the fiber  20  with respect to the resin  23  are substantially equal to each other, at two positions separate by an integer multiple of 0 or more of its period, i.e. Pg 1 . In addition, the volume ratios of the fiber  20  with respect to the resin  23  are substantially equal to each other, between at a position separate by ½ of the period, which is Pg 1 /2, and at a position separate by a distance resulting from adding ½ of the period to n k -multiple of the distance Pg 1  (the period), which is Pg 1 (n k +½). 
     For this reason, an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 . 
     Seventh Example Embodiment 
     In examples of the first to sixth example embodiments, the transmission line  12  has a positive signal line  10  and a negative signal line  11  that are parallel to each other. However, the sections of the transmission line  12  may be partially not parallel. 
     As illustrated in  FIG. 13 , on the printed wiring board  170  according to seventh example embodiment of the present invention, the positive signal line section S 1   2i+1  extends along an imaginary straight line that is separate by Pg 1 /2 from an imaginary straight line on which the positive signal line section S 1   2i  extends. The negative signal line section S 1 ′ 2i+1  extends along an imaginary straight line that is separate by Pg 1 /2 from an imaginary straight line on which the negative signal line section S 1 ′ 2i  extends. Here, a direction from the positive signal line section S 1   2i  to the positive signal line section S 1   2i+1  is reverse to a direction from the negative signal line section S 1 ′ 2i  to the negative signal line section S 1 ′ 2i+1 . That is, a distance between the positive signal line section S 1   2i+1  and the negative signal line section S 1 ′ 2+1  is larger, by Pg 1 , than a distance between the positive signal line section S 1   2i  and the negative signal line section S 1 ′ 2i . 
     Here, a distance between an imaginary straight line on which the odd-numbered negative signal line section S 1 ′ 2i−1  extends and an imaginary straight line on which the odd-numbered negative signal line section S 1 ′ 2i+1  extends is Pg 1 . Here, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 , the volume ratios of the fiber  20  with respect to the resin  23  are substantially equal to each other, at two positions separate by its period, i.e. Pg 1 . 
     For this reason, an effect of the difference in permittivity between the resin  23  and the fiber  20  in the transmission line  12  on the propagation delay is small, due to the symmetry and periodicity of the volume ratio of the fiber  20  with respect to the resin  23 . 
     The seventh example embodiment is not limited to the configuration described above, and can be combined with the configuration of the sixth example embodiment. The positive signal line section S 1   j  extends along a plurality of mutually parallel imaginary straight lines which are aligned with a glass cloth interval Pg 1  therebetween, and the positive signal line section S 1   k  extends along a plurality of mutually parallel imaginary straight lines which are separate by Pg 1 (n k +½) from the imaginary straight lines on which the positive signal line section S 1   j  extends and are parallel to the positive signal line section S 1   j . Similarly, in the case of negative signal lines, the negative signal line section S 1 ′ j  extends along a plurality of mutually parallel imaginary straight lines which are aligned with a glass cloth interval Pg 1  therebetween, and the negative signal line section S 1 ′ k  extends along a plurality of mutually parallel imaginary straight lines which are separate by Pg 1 (n′ k +½) from the imaginary straight lines on which the negative signal line section S 1 ′ j  extends and are parallel to the negative signal line section S 1 ′ 3 . Here, “n k ” and “n′ k ” are an integer equal to or more than 0, and they may not be equal to each other. 
     So far, example embodiments of the present invention have been explained, which do not limit the present invention. 
     For example, as an example of placing the fibers  20  configuring the insulation layers  25  and  26 , to be parallel to each other, a configuration has been exemplified, in which a position of the fibers  20  configuring the insulation layer  26  is located above the fibers  20  configuring the insulation layer  25 . However, as illustrated in  FIG. 14 , a position of the fibers  20  configuring the insulation layer  26  does not necessarily have to be located above the fibers  20  configuring the insulation layer  25 . 
     In addition, in the above-described example embodiments, the line width of the positive signal line  10  and the negative signal line  11  is exemplified as 0.1 to 0.2 mm. However, any line width may be adopted. 
     In addition, in the above-described embodiments, the interval Dp between the positive signal line  10  and the negative signal line  11  is exemplified as satisfying Dp&lt;Pg 1 , however may be Dp≥Pg 1 . From the viewpoint of the differential skew, the relation Dp=Pg 1 /2 is desirable. 
     In addition, in the above-described embodiments, a strip line is exemplified as the transmission line. However, this is not limiting, and the transmission line may be micro strip line or a co-planer line. A micro strip line includes an insulation layer  25 , a ground layer  24  that is in contact with the insulation layer  25 , and a transmission line  12 , instead of including an insulation layer  26  and a ground layer  24  that is in contact with the insulation layer  26 . In addition, a co-planer line includes an insulation layer  25 , a transmission line  12 , and a ground by way of conductors such as copper foil at a certain interval therebetween, and aligned outside of and to the left and right of the transmission line  12 , sandwiching the transmission line  12  therebetween. 
     In addition, in the above-described example embodiment, a single-layer printed wiring board is exemplified as the printed wiring board. However, a multilayer circuit board may be adopted, which is formed by layering single-layer printed wiring boards. 
     In addition, in the determining method of a wiring pattern, having been described above, the angle θ was exemplified as an angle formed between the positive signal line section S 1   i  and the line  10   c . However, the angle θ may be an angle formed between the fiber  20  and the line  10   c.    
     In addition, in the determining method of a wiring pattern, having been described above, as an instructing unit to instruct the glass cloth interval Pg, the interval Dp between the positive signal line and the negative signal line, the maximum value L max  of the line length L i  of the positive signal line section, and the angle θ, inputting through the operating unit  201  has been exemplified. However, a configuration is also possible in which they are accumulated in the auxiliary storage unit  204  in advance, and are read by the controller  202  where necessary at the execution of a program. 
     In addition, in the determining method of a wiring pattern, having been described above, the maximum value L max  of the line length of L i  of the positive signal line section is exemplified to be input. However, a configuration is also possible in which the minimum value L min  or a rough line length L req  is input. When inputting the minimum value L min , the conditions of L 2i−1 ≤L max  and L 2i ≤L max  are changed to the conditions of L 2i−1 ≥L min  and L 2 ≥L min . In addition, when inputting the line length L req , the conditions of L 2i−1 ≤L max  and L 2i ≤L max  are changed to the condition to select values of L 2i−1  and L 2i , to be closest to the line length L req . 
     So far, some example embodiments and their modification examples according to the invention according to the present application have been described. However, the printed wiring board according to the invention according to the present application does not have to include all the exemplified configurations. 
     For example, the printed wiring board illustrated in  FIG. 15  may be achieved by a configuration that includes: 
     an insulation layer configured by a glass cloth  22  in which the fibers  20  and  21  are woven, and a resin with which the glass cloth  22  is impregnated; 
     a positive signal line  10  which is first wiring and is configured by
         a line in a positive signal line section S 1   j , which is a first line extending on an imaginary straight line that is parallel to the fiber  20  woven into the glass cloth  22 ,   a line in a positive signal line section S 1   k  that is a second line extending on an imaginary straight line that is parallel to a line in the positive signal line section S 1   j , which is separate from an imaginary straight line on which the positive signal line section S 1   j  extends, by a distance resulting from adding ½ of the interval Pg 1  of the fiber  20  to an integer multiple equal to 0 or more of the interval of the fiber  20 , and   a third line connecting a line in the positive signal line section S 1   j  and a line in the positive signal line section S 1   k ; and       

     a negative signal line  11  which is second wiring and is configured by
         a line in a negative signal line section S 1 ′ j  extending on an imaginary straight line that is parallel to a line of the positive signal line section S 1   j ,   a negative signal line section S 1 ′ k  that is a fifth line extending on an imaginary straight line that is parallel to a line in the negative signal line section S 1 ′ j , which is separate from an imaginary straight line on which the negative signal line section S 1 ′ j  extends, by a distance resulting from adding ½ of the interval of the fiber to an integer multiple equal to 0 or more of the interval Pg 1  of the fiber  20 , and   a sixth line that connects between lines configuring a line in the negative signal line section S 1 ′ j  and a line in the negative signal line section S 1 ′ k , where       

     a total line length of the line in the positive signal line section S 1   j  and a total line length of the line in the positive signal line section S 1   k  are equal to each other, 
     a total line length of the line in the negative signal line section S 1 ′ j  and a total line length of the line in the negative signal line section S 1 ′ k  are equal to each other, 
     a total line length of the line in the negative signal line section S 1 ′ j  and the line in the negative signal line section S 1 ′ k  and a total line length of the line in the positive signal line section S 1   j  and the line in the positive signal line section S 1   k  are equal to each other, and 
     a line length of the positive signal line  10  and a line length of the negative signal line  10  are equal to each other. 
     Note that the positive signal line  10  and the negative signal line  11  are disposed on the insulation layer. In addition, any polarity of a signal may be adopted, which may be reversed. 
     Note that a part or all of the example embodiments described above can also be expressed as in the following Supplementary notes; however, the present invention exemplified in the above example embodiments is not limited to the following Supplementary notes. 
     (Supplementary Note 1) 
     A printed wiring board characterized by comprising: 
     an insulation layer configured by a glass cloth in which fiber is woven, and a resin with which the glass cloth is impregnated; 
     first wiring configured by
         a first line extending on an imaginary straight line that is parallel to the fiber woven in the glass cloth,   a second line extending on an imaginary straight line that is parallel to the first line, the second line being separate from the imaginary straight line on which the first line extends, by a distance resulting from adding ½ of an interval of the fiber to an integer multiple equal to 0 or more of the interval of the fiber, and   a third line connecting lines configuring the first line and the second line; and       

     second wiring configuring by
         a fourth line extending on an imaginary straight line that is parallel to the first line,   a fifth line on an imaginary straight line that is parallel to the fourth line, the fifth line being separate from the imaginary straight line on which the fourth line extends, by a distance resulting from adding ½ of an interval of the fiber to an integer multiple equal to 0 or more of the interval of the fiber, and   a sixth line connecting lines configuring the fourth line and the fifth line, wherein       

     a total line length of the first line and a total line length of the second line are equal to each other, 
     a total line length of the fifth line and a total line length of the sixth line are equal to each other, 
     a total line length of the fourth line and the fifth line and are a total line length of the first line and the second line are equal to each other, and 
     a line length of the first wiring and a line length of the second wiring are equal to each other. 
     (Supplementary Note 2) 
     The printed wiring board according to Supplementary note 1, characterized in that 
     the first line extends along mutually equal imaginary straight lines, and 
     the fourth line extends along mutually equal imaginary straight lines, 
     (Supplementary Note 3) 
     The printed wiring board according to Supplementary note 1 or 2, characterized in that 
     the first line extends along mutually equal imaginary straight lines, 
     the second line extends along mutually equal imaginary straight lines, 
     the fourth line extends along mutually equal imaginary straight lines, and 
     the fifth line extends along mutually equal imaginary straight lines. 
     (Supplementary Note 4) 
     The printed wiring board according to any one of Supplementary notes 1 to 3, characterized in that 
     the third line is configured by a line whose one end is connected to the first line, the other end thereof being connected to the second line, and 
     the sixth line is configured by a line whose one end is connected to the fourth line, the other end thereof being connected to the fifth line. 
     (Supplementary Note 5) 
     The printed wiring board according to any one of Supplementary notes 1 to 4, characterized in that 
     the third line is formed of a straight line, and 
     the sixth line is formed of a straight line. 
     (Supplementary Note 6) 
     The printed wiring board according to any one of Supplementary notes 1 to 5, characterized in that 
     the third line is formed of a straight line, 
     an angle θ formed between the third line and the first line is 0&lt;θ&lt;90°, 
     the sixth line is formed of a straight line, and 
     an angle θ formed between the sixth line and the fourth line is 0&lt;θ&lt;90°. 
     (Supplementary Note 7) 
     The printed wiring board according to any one of Supplementary notes 1 to 6, characterized in that 
     the first wiring and the second wiring are configured by lines that are parallel to each other. 
     (Supplementary Note 8) 
     The printed wiring board according to Supplementary note 7, characterized in that 
     an interval between the first wiring and the second wiring is configured shorter than the interval of the fiber. 
     (Supplementary Note 9) 
     The printed wiring board according to any one of Supplementary notes 1 to 8, characterized in that 
     an interval between the first wiring and the second wiring is equal to ½ of the interval of the fiber. 
     (Supplementary Note 10) 
     An electronic circuit characterized by comprising a printed wiring board according to any one of Supplementary notes 1 to 9. 
     (Supplementary Note 11) 
     A determining method of wiring of a printed wiring board according to any one of Supplementary notes 1 to 9, characterized by comprising: 
     a step of extracting, by a controller, a transmission line that is parallel to the fiber, from among a plurality of transmission lines configuring a wiring pattern; 
     a step of designating, by a designating unit, an angle formed between the fiber and the third line; 
     a step of calculating, by the controller, a line length of the third line and a length of a component of the third line that is parallel to the fiber, under a condition that i) a length resulting from adding ½ of the interval of the fiber to an integer multiple equal to 0 or more of the interval of the fiber is equal to a length of a component of the third line that is orthogonal o the fiber, and ii) the angle designated by the designating unit; 
     a step of calculating, by the controller, a line length of the first line and a line length of the second line, under a condition that i) a line length of the first line is equal to a line length of the second line, ii) a total length of a length of a component of the third line that is parallel to the fiber, the line length of the first line, and the line length of the second line is equal to a line length of the transmission line; 
     a step of determining, by the controller, the first wiring configured by the first line, the second line, and the third line, under a condition that i) the first line is configured by a line that is parallel to the fiber, ii) the second line is configured by a line that is parallel to the first line, and iii) a distance between an imaginary straight line that is an extension of the first line and the second line is configured by a length of a component of the third line that is orthogonal to the fiber, and iv) the angle is equal to an angle formed between the imaginary straight line that is an extension of the first line and the third line; and 
     a step of determining the second wiring by the controller, under a condition that i) the second wiring is configured by a line that is parallel to the first wiring, ii) a line length of the second wiring is equal to a line length of the first wiring. 
     (Supplementary Note 12) 
     A program for executing a method according to Supplementary note 11. 
     So far, the present invention has been explained by way of the above-described exemplary embodiments. However, the present invention is not limited to the above-described example embodiments. In other words, the present invention can be applied to various modes which a person skilled in the art can conceive of, within the scope of the present invention. 
     This application is based upon and claims the benefit of priority from Japanese patent application No. 2006-56292, filed on Mar. 18, 2016, the disclosure of which is incorporated herein in its entirety by reference. 
     REFERENCE SIGNS LIST 
     
         
         
           
               10  positive signal line 
               11  negative signal line 
               12  transmission line 
               20  fiber 
               21  fiber 
               22  glass cloth 
               23  resin 
               24  ground layer 
               25  insulation layer 
               26  insulation layer 
               31  position at which volume ratio of fiber with respect to resin is high 
               32  position separated from position  31  by Pg 1 /2 
               33  position at which volume ratio of fiber with respect to resin is medium 
               34  position separate from position  33  by Pg 1 /2 
               35  position at which volume ratio of fiber with respect to resin is low 
               36  position separate from position  35  by Pg 1 /2 
               37   a  one end of positive signal line section S 1   1    
               37   b  position at which positive signal line section S 1   1  and line  10   c  are connected 
               38   a  position at which positive signal line section S 1   2  and line  10   c  are connected 
               38   b  position at which positive signal line section S 1   2  and line  10   d  are connected 
               39   a  position at which positive signal line section S 1   j  and line  10   d  are connected 
               40  signal through hole 
               41  signal through hole 
               42  through hole 
               50  wiring section in vicinity of region immediately below LSI 
               51  wiring section separate from region immediately below LSI 
               110  printed wiring board according to first example embodiment of the present invention 
               120  printed wiring board according to second example embodiment of the present invention 
               130  printed wiring board according to third example embodiment of the present invention 
               140  printed wiring board according to fourth example embodiment of the present invention 
               150  printed wiring board according to fifth example embodiment of the present invention 
               160  printed wiring board according to according to sixth example embodiment of the present invention 
               170  printed wiring board according to according to seventh example embodiment of the present invention 
               200  processor 
               201  operating unit 
               202  controller 
               203  main storage unit 
               204  auxiliary storage unit 
               205  display