JP2010199512A - Printed board and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To bring delay time of a signal flowing in a short wiring close to the delay time of a signal flowing in a long wiring. <P>SOLUTION: The apparatus comprises a first wiring 113 having end portions 111, 112, in which length to the end portions 112 from the end portions 111 is L1, a second wiring 123 having end portions 121, 122, in which length to the end portions 122 from the end portions 121 is L2, and delay time adjusting sections 124A, 124B prepared in the end portions 121, 122. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a printed circuit board for adjusting a delay time of a signal flowing in a wiring, and an electronic apparatus having the printed circuit board.

  Even if a signal is input from the input side of the wiring, a delay corresponding to the wiring length occurs until the signal is output to the output side of the wiring. The time from when a signal is input until the signal is output to the output side is called a delay time.

  Usually, the circuit is designed in consideration of the delay time. However, a large variation in delay time may cause malfunction. In order to suppress variations in delay time, the lengths of a plurality of wirings may be made uniform (see Patent Document 1).

JP-A-6-124322

  However, when the wiring density is high, it is difficult to secure a space for routing the wiring in order to align the wiring length. As a result, it may be difficult to make the wiring lengths uniform, or the structure of the wiring may become complicated by stretching the shorter wiring into a bellows shape.

  An object of the present invention is to provide a printed circuit board capable of bringing a signal flowing in a short wiring closer to a delay time of a signal flowing in a long wiring, and an electronic apparatus having the printed circuit board.

  A printed circuit board according to an example of the present invention includes a first end portion provided with a pad or a plug and a second end portion provided with a pad or a plug, and the second end from the first end portion. A first wiring having a first length between the first portion, a third end portion provided with a pad or a plug, and a fourth end portion provided with a pad or a plug, Provided in at least one of the third wiring and the fourth end, the second wiring having a second length shorter than the first length from the third end to the fourth end And a delay time adjusting unit having a third length.

  An electronic apparatus having a printed circuit board according to an example of the present invention, wherein the printed circuit board has a first end portion provided with a pad or a plug and a second end portion provided with a pad or a plug. A first wiring having a first length from the first end to the second end, a third end provided with a pad or plug, and a pad or plug are provided. A second end, and a length between the third end and the fourth end is a second length shorter than the first length, and the third end A first adjustment unit connected to the first and / or second adjustment unit connected to the fourth end, the total length of the first delay time adjustment unit and the second delay time adjustment unit And a delay time adjustment unit having a third length.

  According to the present invention, a signal flowing in a short wiring can be brought close to a delay time of a signal flowing in a long wiring.

1 is a perspective view illustrating an appearance of an electronic device according to an embodiment of the present invention. The figure which shows a part of printed circuit board concerning one Embodiment of this invention. The figure which shows a part of printed circuit board concerning one Embodiment of this invention. The figure which shows a part of printed circuit board concerning one Embodiment of this invention. The figure which shows a part of printed circuit board concerning one Embodiment of this invention. The figure which shows the position of the driver, receiver, and delay time adjustment part with respect to the wiring which performed the simulation. The figure which shows the simulation result in case the length of a delay time adjustment part is 10 mm. The figure which shows the simulation result in case the length of a delay time adjustment part is 20 mm. The figure which shows the simulation result in case the length of a delay time adjustment part is 30 mm.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, the configuration of an electronic device according to an embodiment of the present invention will be described with reference to FIG. This electronic apparatus is realized as a portable notebook personal computer 10 that can be driven by a battery.

  FIG. 1 is a perspective view of the notebook personal computer 10 with the display unit opened. The computer 10 includes a computer main body 11 and a display unit 12. The display unit 12 incorporates a display panel composed of an LCD 17 (Liquid Crystal Display) and a backlight, and the display screen of the LCD 17 is positioned substantially at the center of the display unit 12. The LCD 17 is composed of a transmissive liquid crystal panel.

  The display unit 12 is supported by the computer main body 11, and is freely attached to the computer main body 11 between an open position where the upper surface of the computer main body 11 is exposed and a closed position covering the upper surface of the computer main body 11. ing. The computer main body 11 has a thin box-shaped casing, and a keyboard 13, a power button 14 for turning on / off the computer 10, an input operation panel 15, a touch pad 16, and the like are arranged on the upper surface thereof. Has been.

  The input operation panel 15 is an input device for inputting an event corresponding to a pressed button, and includes a plurality of buttons for starting a plurality of functions for starting a plurality of functions.

FIG. 2 is a plan view showing a configuration of a part of a printed wiring board on which a semiconductor chip provided in the electronic device shown in FIG. 1 is mounted.
As shown in FIG. 2, the first wiring 113, the second wiring 123, and the third wiring 133 are provided on the surface of the printed wiring board 100. The first wiring 113 has an end 111 and an end 112. The length between the end 111 and the end 112 is L1. The second wiring 123 has an end 121 and an end 122. The length of the wiring 123 between the end portion 121 and the end portion 122 is L2. The third wiring 133 has an end 131 and an end 132. The length of the wiring 133 between the end 131 and the end 132 is L3. The end portions 111, 112, 121, 122, 131, 132 are defined by pads or plugs (via plugs, through plugs, etc.).

  The relationship among the length L1 of the first wiring 113, the length L2 of the second wiring 123, and the length L3 of the third wiring 133 is L1> L2> L3. The lengths of the three wirings 113, 123, and 133 are different from each other. The delay time of the signal flowing through the wiring becomes longer as the wiring length is longer. Therefore, the delay time of the first wiring 113 is the longest, and the delay time of the third wiring 133 is the shortest.

  A pair of ends of the wiring having the longest wiring length (first wiring 113 in this embodiment) is defined as a first end and a second end. A pair of ends of the wiring having a short wiring length (in the case of this embodiment, the second wiring 123 and the third wiring 133) are defined as a third end and a fourth end.

  In order to adjust the delay time, stubs 124 </ b> A and 124 </ b> B as delay time adjustment units are connected to the end of the second wiring 123. Similarly, stubs 134 </ b> A and 134 </ b> B as delay time adjustment units are connected to the end of the third wiring 133. Adding a stub has a delay effect. The stubs 124 </ b> A and 124 </ b> B are delay time adjustment units for the second wiring 123. Similarly, the stubs 134A and 134B are delay time adjusting units for the third wiring 133. In addition, in order to adjust the delay time, a member connected to one end is an adjustment unit, and the entire adjustment unit provided for the wiring is a delay time adjustment unit. In addition, the length (third length) of the delay time adjustment unit is defined by the sum of the lengths of the adjustment units connected to the pair of ends.

  In FIG. 2, a stub 124A as a first adjustment unit is electrically connected to an end 121 to which the second wiring 123 is connected. In addition, a stub 124B as a second adjustment unit is electrically connected to the end 122 to which the second wiring 123 is connected. Similarly, a stub 134A as a first adjustment unit is electrically connected to an end 131 to which the third wiring 133 is connected. A stub 134B as a second adjustment unit is electrically connected to an end 132 to which the third wiring 133 is connected. In the case of the wiring 123, the length (third length) of the delay time adjustment unit is defined by the sum of the lengths of the stubs 124A and 124B connected to the ends. In the case of the wiring 133, the length (third length) of the delay time adjustment unit is defined by the sum of the lengths of the stubs 134A and 134B connected to the ends.

  In addition, it is not necessary to connect a stub to each edge part connected to wiring. You may connect a stub to one of a pair of edge part connected to wiring. In FIG. 3, a stub is not connected to the end 121 of the second wiring 132, and a stub 125 as a second adjustment unit is connected to the end 122. In addition, a stub is not connected to the end portion 131 of the wiring 133, and a stub 135 as a second adjustment unit is connected to the end portion 132. A configuration in which a stub is connected to the end 121 and a stub is not connected to the end 122 may be used. Similarly, a configuration in which a stub is connected to the end 131 and a stub is not connected to the end 132 may be employed.

  Further, a part of the adjustment unit may be a plug. As shown in FIG. 4, a second adjustment unit including a stub 126 </ b> A and a through plug 126 </ b> B is connected to the end 122 as the second end. A stub 126 </ b> A as a first adjustment wiring is connected to the end portion 122. A plug 126B as an adjustment plug is connected to the stub 126A. A second adjustment unit including a stub 136A and a through plug 136B is connected to the end 132 as the second end. A stub 136 </ b> A as the first adjustment wiring is connected to the end portion 132. A through plug 136B as an adjustment plug is connected to the stub 136A. The length of the adjustment portion connected to the end portion 122 is defined by the sum of the length of the stub 126A and the length of the through plug 136B. Similarly, the length of the adjusting portion connected to the end portion 132 is defined by the sum of the length of the stub 136A and the length of the through plug 136B.

  Note that, instead of connecting the adjustment unit configured by the stub 126A and the through plug 126B to the end 122, the adjustment unit may be connected to the end 121 as the second end. Moreover, you may connect the adjustment part comprised from a stub and a through plug to the edge parts 121 and 122, respectively. Similarly, instead of connecting the adjustment portion configured by the stub 136A and the through plug 136B to the end portion 132, the adjustment portion may be connected to the end portion 131 as the second end portion. You may connect the adjustment part comprised from a stub and a through plug to the edge parts 131 and 132, respectively. A via plug may be used instead of the through plug. In the case of the wiring 133, the length of the adjustment portion is defined by the sum of the length of the stub 137A connected to the end portion, the length of the plug 137B, and the length of the via plug 137C.

  Moreover, you may provide a part of adjustment part in another layer. For example, as illustrated in FIG. 5, a second adjustment unit including a stub 137A, a via plug 137B, and a stub 137C is connected to the end 132 serving as the second end. A stub 137A as a first adjustment wiring is connected to the end 132 as the second end. A via plug 137B as an adjustment plug is connected to the stub 137A. A stub 137C as a second adjustment wiring is connected to the via plug 137B.

  Instead of connecting the adjustment unit configured by the stub 137A, the via plug 137B, and the stub 137C to the end 132, the adjustment unit may be connected to the end 131 as the second end. You may connect the adjustment part comprised from a stub, a via plug, and a stub to the edge parts 131 and 132, respectively.

  Next, the influence of the length of the delay time adjustment unit and the direction in which the signal flows on the delay time will be described.

  In order to investigate the influence on the delay time, a signal output from the input side (driver) of the wiring and then output to the output side (receiver) of the wiring was obtained by simulation. The simulation was performed by setting the length of the reference wiring to 200 mm and the length of the wiring without the delay time adjustment unit to 180 mm. HSPICE (registered trademark) was used for the simulation.

  In order to confirm the influence of the length of the delay time adjusting unit on the delay time, a simulation was performed in the case where the length of the delay time adjusting unit was 10 mm, 20 mm, and 30 mm.

  In addition, in order to investigate the influence of the signal flow direction on the delay time, the reference length of wiring, the wiring without the delay time adjustment unit, the wiring with the delay time adjustment unit on the receiver side, the driver side The wiring provided with the delay time adjustment unit and the signal output to the receiver side when the delay time adjustment unit is provided on both the receiver side and the driver side were obtained by simulation.

  In the case of a wiring having a reference length and a wiring not provided with a delay time adjustment unit, as shown in FIG. 6A, a driver 142 that outputs a signal to the end of the wiring 141 and a signal output by the driver 142 The simulation was performed on the assumption that the receiver 143 for receiving the signal is provided.

  In the case of a wiring provided with a delay time adjustment unit on the receiver side, as shown in FIG. 6B, a driver 142 and a receiver 143 are provided at the end of the wiring 151, and a delay is provided at the end of the wiring 151 on the receiver 143 side. The simulation was performed assuming that the stub 154 is provided as the time adjustment unit.

  In the case of a wiring provided with a delay time adjustment unit on the driver side, as shown in FIG. 6C, a driver 142 and a receiver 143 are provided at the end of the wiring 151, and a delay is provided at the end of the wiring 151 on the driver 142 side. The simulation was performed assuming that the stub 164 was provided as the time adjustment unit.

  In the case of a wiring provided with a delay time adjustment unit on both the receiver side and the driver side, as shown in FIG. 6D, a driver 142 and a receiver 143 are provided at the end of the wiring 151, and the driver 151 side of the wiring 151 A simulation was performed on the assumption that a stub 174A was provided as a delay time adjustment unit at the end of the stub, and a stub 174B was provided as a delay time adjustment unit at the end of the wiring 151 on the receiver 143 side.

The simulation results are shown in FIGS. 7 to 9, the horizontal axis indicates the time after the receiver inputs a signal to the wiring, and the vertical axis indicates the voltage of the signal output to the driver side.
FIG. 7 shows a simulation result when the length of the delay time adjustment unit is 10 mm. When the length of the delay time adjustment unit is 10 mm, the combined length of the wiring and the delay time adjustment unit is 10 mm shorter than the reference wiring length (200 mm). The waveform indicated by the solid line L200 is the simulation result of the reference wiring, the waveform indicated by the broken line L180 is the simulation result of the wiring not provided with the delay time adjustment unit, and the waveform indicated by the one-dot broken line L180_S10R is provided with the stub 154 on the receiver side. As a result of the wiring simulation, the waveform indicated by the two-dot broken line L180_S10D is the simulation result of the wiring provided with the stub 164 on the driver side, and the waveform indicated by the broken line L180_S10RD whose solid line portion is longer than L180 is It is the simulation result of the wiring which provided stub 174A, 174B.

  As shown in FIG. 7, it can be seen that the waveforms L180_S10R, L180_S10D, and L180_S10RD are closer to the waveform L200 than the waveform L180. A waveform L180_S10R provided with a delay time adjustment unit on the receiver side is close to the waveform L200. Next, the waveform L180_S10RD in which the delay time adjustment unit is provided on the receiver and driver sides is close to the waveform L200. A waveform L180_S10D in which a delay time adjustment unit is provided on the driver side is the waveform farthest from the waveform L200. Therefore, when the direction of the signal flowing through the wiring is unidirectional, it is preferable to provide a delay time adjustment unit on the receiver side. In addition, when the direction of the signal flowing through the wiring is bidirectional, it is preferable to provide a delay time adjustment unit on the receiver and driver side.

  FIG. 8 shows a simulation result when the length of the delay time adjustment unit is 20 mm. When the length of the delay time adjustment unit is 20 mm, the total length of the wiring and the delay time adjustment unit is equal to the reference wiring length (200 mm). The waveform indicated by the solid line L200 is the simulation result of the reference wiring, the waveform indicated by the broken line L180 is the simulation result of the wiring not provided with the delay time adjustment unit, and the waveform indicated by the one-dot dashed line L180_S20R is provided with the stub 154 As a result of the simulation of the wiring, the waveform indicated by the two-dot broken line L180_S20D is the simulation result of the wiring provided with the stub 164 on the driver side, and the waveform indicated by the broken line L180_S20RD whose solid line part is longer than L180 is It is the simulation result of the wiring which provided stub 174A, 174B.

  As shown in FIG. 8, it can be seen that the waveforms L180_S20R, L180_S20D, and L180_S20RD are closer to the waveform L200 than the waveform L180. Also, up to about 3 V, the waveform L180_S20R in which the delay time adjustment unit is provided on the receiver side is close to the waveform L200. From around 3 V, the waveform L180_S20RD in which the delay time adjustment unit is provided on the receiver and driver sides is close to the waveform L200. A waveform L180_S20D in which a delay time adjustment unit is provided on the driver side is the waveform farthest from the waveform L200. Therefore, when the direction of the signal flowing through the wiring is unidirectional, it is preferable to provide a delay time adjustment unit on the receiver side. In addition, when the direction of the signal flowing through the wiring is bidirectional, it is preferable to provide a delay time adjustment unit on the receiver and driver side.

  FIG. 9 shows a simulation result when the length of the delay time adjustment unit is 30 mm. When the length of the delay time adjustment unit is 30 mm, the combined length of the wiring and the delay time adjustment unit is 10 mm longer than the reference wiring length (200 mm). The waveform indicated by the solid line L200 is the simulation result of the reference wiring, the waveform indicated by the broken line L180 is the simulation result of the wiring not provided with the delay time adjustment unit, and the waveform indicated by the one-dot dashed line L180_S30R is provided with the stub 154 As a result of the wiring simulation, the waveform indicated by the two-dot broken line L180_S30D is the simulation result of the wiring provided with the stub 164 on the driver side. It is the simulation result of the wiring which provided stub 174A, 174B.

  From the results shown in FIG. 7, the direction of the signal flowing through the wiring is one-way, and the length of the wiring based on the length of the delay time adjusting unit and the length of the wiring connecting the delay time adjusting unit to the end is the reference. When the length is shorter than the length, it is preferable to provide a delay time adjustment unit on the receiver side.

  As shown in FIG. 9, it can be seen that the waveforms L180_S30R, L180_S30D, and L180_S30RD are closer to the waveform L200 than the waveform L180. Of the waveforms L180_S30R, L180_S30D, and L180_S30RD, the waveform L180_S30D provided with the delay time adjustment unit on the driver side is closest to the waveform L200. Next, the waveform L180_S30RD in which the delay time adjustment unit is provided on the receiver and driver side is close to the waveform L200. And the waveform L180_S30R which provided the delay time adjustment part in the receiver side is furthest from the waveform L200. Therefore, when the direction of the signal flowing through the wiring is unidirectional, it is preferable to provide a delay time adjustment unit on the driver side. In addition, when the direction of the signal flowing through the wiring is bidirectional, it is preferable to provide a delay time adjusting unit at both ends of the wiring.

  From the result shown in FIG. 9, the direction of the signal flowing through the wiring is one-way, and the length of the wiring based on the length of the delay time adjusting unit and the length of the wiring connecting the delay time adjusting unit to the end is the reference. When longer than the length, it is preferable to provide a delay time adjusting unit on the driver side.

  As shown in FIGS. 7 to 9, by providing the delay time adjustment unit at the end of the wiring, there is an effect of delaying the rise of the signal regardless of the length of the delay time adjustment unit. As a result, the delay time of the signal flowing through the second wiring 112 and the third wiring 113 shorter than the first wiring 113 can be made closer to the delay time of the signal flowing through the first wiring 111.

  Normally, there is an effect that the delay time of the wiring is delayed by the same amount as the wiring length of the stub, but it is necessary if the effective relative dielectric constant of the wiring is different when a plug or a stub is provided as a delay time adjustment unit. The length of the delay time adjustment unit varies.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  DESCRIPTION OF SYMBOLS 10 ... Notebook-type personal computer, 100 ... Printed wiring board, 113 ... 1st wiring, 123 ... 2nd wiring, 133 ... 3rd wiring, 111, 112, 121, 122, 131, 132 ... End part, 124A, 124B , 125, 126A, 137A, 137C, 134A, 134B, 135, 136A ... stubs, 126B, 136B ... through plugs, 137B ... via plugs.

Claims (10)

A first end portion provided with a pad or a plug and a second end portion provided with a pad or a plug, and a length from the first end portion to the second end portion is a first length; A first wire that is long;
A third end portion provided with a pad or a plug and a fourth end portion provided with a pad or a plug, and a length from the third end portion to the fourth end portion is the first end portion; A second wiring having a second length shorter than one length;
A first adjustment unit connected to the third end and / or a second adjustment unit connected to the fourth end; the first delay time adjustment unit and the second delay time adjustment unit; And a delay time adjusting unit whose total length is a third length. The delay time adjustment unit has only the first adjustment unit,
The total length of the second length and the third length is shorter than the first length,
The printed circuit board according to claim 1, wherein a signal flows from the fourth end portion to the third end portion where the first adjustment portion is provided. The delay time adjustment unit has only the first adjustment unit,
The total length of the second length and the third length is longer than the first length,
The printed circuit board according to claim 1, wherein a signal flows from the third end portion where the first adjustment unit is provided to the fourth end portion. A signal flows between the third end and the fourth end,
The printed circuit board according to claim 1, wherein the delay time adjustment unit includes the first adjustment unit and the second adjustment unit.   2. The printed circuit board according to claim 1, wherein the second adjustment unit includes a first adjustment wiring connected to the fourth end portion and an adjustment plug connected to the first adjustment wiring. .   The printed circuit board according to claim 5, wherein the second adjustment unit further includes a second adjustment wiring that is provided in a different layer from the first adjustment wiring and is connected to the adjustment plug. An electronic device having a printed circuit board,
The printed circuit board is
A first end portion provided with a pad or a plug and a second end portion provided with a pad or a plug, and a length from the first end portion to the second end portion is a first length; A first wire that is long;
A third end portion provided with a pad or a plug and a fourth end portion provided with a pad or a plug, and a length from the third end portion to the fourth end portion is the first end portion; A second wiring having a second length shorter than one length;
A first adjustment unit connected to the third end and / or a second adjustment unit connected to the fourth end; the first delay time adjustment unit and the second delay time adjustment unit; An electronic device comprising: a delay time adjustment unit having a total length of a third length. The delay time adjustment unit has only the first adjustment unit,
The total length of the second length and the third length is shorter than the first length,
The electronic apparatus according to claim 7, wherein a signal flows from the fourth end portion to the third end portion where the first adjustment portion is provided. The delay time adjustment unit has only the first adjustment unit,
The total length of the second length and the third length is longer than the first length,
The electronic apparatus according to claim 7, wherein a signal flows from the third end where the first adjustment unit is provided to the fourth end. A signal flows between the third end and the fourth end,
The electronic apparatus according to claim 7, wherein the delay time adjustment unit includes the first adjustment unit and the second adjustment unit.

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