JP2009224489A - Wiring substrate equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide wiring substrate equipment composed of two differential signal lines wired so as to be parallel to each other, wherein a difference of wiring path lengths is absorbed for a pair of differential signal lines about which regions with different mutual wiring path lengths are prepared to resolve a delay time difference in signals propagation, thereby improving the quality of signal transmission. <P>SOLUTION: Two or more electronic components Sa and Sb are mounted on a wiring substrate 1, to which two differential signal lines G composed of a first differential signal line Ga and a second differential signal line Gb are wired parallel to each other, a dividing region Z is formed in a halfway portion of the pair of differential signal lines, a delay wire object 10 is mounted in this dividing region, on which a first delay wire path 11 and a second delay wire path 12 are prepared that have the same wiring path length, and respective ends of these delay wiring paths and the divided pair of differential signal lines are connected. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wiring board device that is mounted on, for example, a mobile phone and transmits a signal between two electronic components by a differential signal transmission method.

  In general, a so-called “single-end transmission method” is employed to transmit a signal between two electronic components. This is because one signal line is connected to two electronic components, a high-level potential signal (hereinafter referred to as “H signal”) and a low-level potential signal (hereinafter referred to as “H” signal) from the electronic component on the driver side. , Referred to as “L signal”) alternately to the one signal line.

  The signal line alternately transmits the H signal and the L signal to the electronic component on the receiver side. The electronic component on the receiver side receives these H and L signals and operates, for example, an LSI logic circuit.

  This single-ended transmission method has no problem as a signal transmission means, but the potential difference between the H signal and the L signal is large, the signal amplitude is large, and the waveform at the time of signal switching is not clear. Therefore, noise is likely to occur and a large number of signals cannot be taken per unit time. That is, there is a problem that a large amount of information cannot be transmitted quickly.

Therefore, in recent years, signal transmission means called “differential signal transmission system” has come to be adopted. In this case, two electronic components are connected by two differential signal lines of P channel wiring and N channel wiring.
First, an H signal is sent from the electronic component on the driver side to the P channel wiring, and an L signal is sent to the N channel wiring. Thereafter, an L signal is sent from the electronic component on the driver side to the P channel wiring, and an H signal is sent to the N channel wiring.

Each signal is sent to an electronic component on the receiver side via a P-channel wiring and an N-channel wiring. The electronic component on the receiver side receives these H and L signals and operates, for example, an LSI logic circuit.
Specifically, as shown in FIG. 8 (A), signals having opposite phases (also referred to as “reverse phases”) obtained by reversing the logical values from the electronic components on the driver side are shown in FIG. 8 (B). The two differential signal lines Ga and Gb are input to the pair. In the electronic component on the receiver side, as shown in FIG. 8C, data is identified by the potential difference between the signals transmitted from the differential signal lines Ga and GB.

  In such a differential signal transmission method, the amplitude width of the signal transmitted by each differential signal line can be smaller than that in the single-end transmission method. Even if there is noise from the outside, the difference is guaranteed, so it has a strong characteristic against noise. Many signals can be transmitted per unit time, and there is an advantage that a larger amount of information can be transmitted faster.

However, this differential signal transmission system has the following limitations.
That is, since signals are sent using the two differential signal lines Ga and Gb, there is a difference in signal transmission time between the differential signal lines Ga and Gb, or a timing shift, etc. A phenomenon called so-called skew may occur.

  As shown in FIG. 9, the ideal timing is that the L signal is originally transmitted with no skew (indicated by a solid line) with respect to the H signal. However, due to reasons described later, there may be a skew of a time as shown by b line (one-dot chain line) or a skew of 2a time as shown by c line (two-dot chain line).

  FIG. 10 is a waveform of the potential difference between the signals flowing in the two differential signal lines shown in FIG. 9. The waveform line A indicated by the thick line is in a state without skew, and the waveform line B indicated by the alternate long and short dash line is the b line. When there is a skew indicated, a waveform line C indicated by a two-dot chain line is when there is a skew indicated by the c line. Threshold values E and F are defined for identifying the H signal and the L signal. The H signal is equal to or higher than the threshold value E, and the L signal is equal to or lower than the threshold value F.

  Any of the waveform lines A to C has a sufficient time below the threshold F, so that there is no problem in the determination. Further, in order to identify the H signal equal to or higher than the threshold F, the time Da exceeding the threshold F is long when there is no skew indicated by the waveform line A. Therefore, there is sufficient time to apply a trigger signal for discriminating data, and the data transmission quality can be kept high.

  However, the waveform line B has a short time Db exceeding the threshold F, and the waveform line C has a very short time Dc exceeding the threshold F. Thus, as the skew increases, the time for applying a trigger signal for discriminating data becomes insufficient, the time during which data can be discriminated is shortened, and the signal transmission quality deteriorates.

  In the differential signal transmission method, the cause of the skew is that the lengths of the two differential signal lines connecting the two electronic components are different from each other, Although the lengths are completely the same, there may be a problem in the structure of the connector that connects the electronic component and the differential signal line pair.

When there is no problem in the structure of the latter connector, [Patent Document 1] responds in a state where the lengths of the two signal lines connecting the two electronic components are different from each other. Yes. That is, according to the present invention, a plurality of sets of differential signal line pairs formed on a printed wiring board meander in a zigzag manner so that the delay wiring path lengths are substantially the same.
JP 2004-325820 A

  However, the technique of [Patent Document 1] is in the case where there are no obstacles (electrical parts, etc.) between two electronic components, and a plurality of differential signal line pairs can be formed in a zigzag manner in an orderly manner. Limited. Actually, it is an ordinary configuration that another electronic component or electrical component is interposed between two electronic components.

  At this time, the middle part of the differential signal line pair is bent to bypass the printed wiring layout. Alternatively, one differential signal line is straight and only the other differential signal line must be bent. In any case, the length of one differential signal line is often different from the length of the other differential signal line, which causes the aforementioned skew.

  For example, there is a wiring board device shown in FIG. That is, the first electronic component Sa and the second electronic component Sb are mounted at positions separated from each other on the wiring board. A differential signal line pair G composed of a first differential signal line Ga and a second differential signal line Gb that electrically connect the first and second electronic components Sa and Sb to each other is printed wiring. Has been.

  Almost most of the first differential signal line Ga and the second differential signal line Gb are formed in a straight line with each other and in parallel with each other. Therefore, the parallel path length between the two differential signal lines Ga and Gb can be made substantially the same by forming the parallel portion meandering as in [Patent Document 1].

  However, here, only the first differential signal line Ga is provided with bent portions K at both ends thereof. When the wiring path length of the first differential signal line Ga is L1 (mm) and the wiring path length of the second differential signal line Gb is L2 (mm), the first differential signal line Ga has two bends. Since the portion K is formed, the wiring path length L1 is longer than the wiring path length L2 of the second differential signal line Gb.

Under the above conditions, the transmission time (t1: s) of the signal transmitted (propagated) between the first electronic component Sa and the second electronic component Sb on the first differential signal line Ga, and the second difference A transmission time (t2: s) of a signal transmitted (propagated) between the first electronic component Sa and the second electronic component Sb on the dynamic signal line Gb is obtained.
First differential signal line Ga: t1 (s) = L1 (mm) / Vg (m / s)
Second differential signal line Gb: t2 (s) = L2 (mm) / Vg (m / s)
The Vg (m / s) is a phase velocity. That is, it is a phase amount that a signal advances (changes) per unit time, and is a value determined by the physical property value of the wiring board and the line width of the differential signal line. As described above, if the lengths L1 and L2 of the differential signal lines to be paired are different, the transmission times t1 and t2 are also different, which causes the skew described above.

  Even if the wiring path lengths of most of the differential signal lines Ga and Gb can be made the same by using the technique of [Patent Document 1], the wiring path is connected to a part of the mutual differential signal lines Ga and Gb. If there is a place where the length is slightly different (such as the bent portion K), the entire wiring path length will be different as a result. For this reason, the phase velocities of the differential signal lines are different, and it is impossible to prevent the quality deterioration of the differential signal transmission.

  The present invention has been made on the basis of the above circumstances, and an object of the present invention is to be composed of two differential signal lines that are wired in parallel to each other, where the differential signal lines have different wiring path lengths. It is intended to provide a wiring board device that absorbs a difference in wiring path length with respect to a differential signal line pair formed, eliminates a delay time difference in signal propagation, and improves signal transmission quality. .

  In order to satisfy the above-described object, the present invention mounts a plurality of electronic components on a wiring board, and wires a differential signal line pair composed of a pair of differential signal lines on the wiring board in parallel with each other. A first delay wiring in which a divided region is formed in the middle of the line pair, a delay wiring body is mounted on the wiring board in the divided region, and the length of each wiring path is set to be the same in this delay wiring body A path and a second delay wiring path are provided, and each end of the delay wiring path is connected to a pair of divided differential signal lines.

  According to the present invention, the delay of signal propagation in the part where the wiring path lengths of the differential signal lines are different is eliminated, the balance disturbance of the differential signal wiring is minimized, and the signal transmission quality is improved. There is an effect of obtaining.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a diagram illustrating a basic configuration of a wiring board device.
In order to employ a so-called “differential signal transmission method”, a pair of (two) differential signal lines are formed between the first electronic component Sa and the second electronic component Sb. The differential signal line pair G is used for connection. One of the differential signal lines is referred to as “first differential signal line Ga”, and the other differential signal line is referred to as “second differential signal line Gb”.

In order to connect the first electronic component Sa and the second electronic component Sb with the shortest distance, if the differential signal line pair G can be wired in a straight line, the wiring path length of the first differential signal line Ga, The two differential signal lines Gb have the same wiring path length, the same signal propagation time, and no skew.
However, since many electronic components are mounted on the wiring board 1, a bent portion K is formed in the middle as shown in the figure. In the bent portion K, when the outer wiring is the first differential signal line Ga and the inner wiring is the second differential signal line Gb, the wiring path length of the first differential signal line Ga at the bent portion K La is longer than the wiring path length Lb of the second differential signal line Gb.

  However, the wiring path lengths of the first and second differential signal lines Ga and Gb at the distance Lc from the first electronic component Sa to one end of the bent portion K are the same. Furthermore, the wiring path lengths of the first and second differential signal lines Ga and Gb at the distance Ld between the other end of the bent portion K and the second electronic component Sb are the same.

  As described above, the total wiring path length Lc + Ld of the first differential signal line Ga and the second differential signal line Gb constituting the differential signal line pair G is the same in both side portions excluding the bent portion K. Therefore, the wiring path lengths La and Lb of the differential signal lines Ga and Gb must be formed substantially the same in the bent portion K.

FIG. 1B is a schematic explanatory view of a part of the wiring board device according to the first embodiment of the present invention.
The first electronic component Sa and the second electronic component Sb are mounted on the plate surface of the wiring board 1 at positions separated from each other. A differential signal line pair G including a first differential signal line Ga and a second differential signal line Gb is connected in parallel with each other from the first electronic component Sa to the second electronic component Sb.

  A portion corresponding to the bent portion K formed in the middle portion of the differential signal line pair G is divided, and a divided region Z is provided. Therefore, the line direction of the differential signal line pair G from the first electronic component Sa to the divided region Z and the line direction of the differential signal line pair G from the divided region Z to the second electronic component Sb. Here, they intersect each other at right angles (90 °).

  The delay wiring body 10 is fitted in the dividing region Z and mounted on the wiring board 1. The delay wiring body 10 may have a plurality of configurations as will be described later, and includes a first delay wiring path 11 and a second delay wiring path 12 each having two wiring patterns. The wiring path length of the first delay wiring path 11 and the wiring path length of the second delay wiring path 12 are the same as each other.

  Connection portions g1 and g2 are provided at both ends of the first delay wiring path 11, and the connection portion g1 on one end side is a division of the first differential signal line Ga wired from the first electronic component Sa. Connected to the edge of the region. The connection part g2 on the other end side is connected to the end part of the divided region of the first differential signal line Ga reaching the second electronic component Sb.

  Connection portions h1 and h2 are also provided at both ends of the second delay wiring path 12, and the connection portion h1 on one end side is divided by the second differential signal line Gb wired from the first electronic component Sa. Connected to the edge of the region. The connection portion h2 on the other end side is connected to the end portion of the divided region of the second differential signal line Gb that reaches the second electronic component Sb.

  The line direction of the differential signal line pair G from the first electronic component Sa to the dividing region Z and the line direction of the differential signal line pair G from the dividing region Z to the second electronic component Sb are: They are orthogonal to each other. If the wiring is as it is, the wiring path length of the first differential signal line Ga that is the outer wiring differs from the wiring path length of the second differential signal line Gb that is the inner wiring at the bent portion K.

However, the portion corresponding to the bent portion K is divided, and the delay wiring body 10 is mounted in the divided region Z. The delay wiring body 10 includes a first delay wiring path 11 and a second delay wiring path 12 which are formed to have the same wiring path length.
As described above, the wiring path length of the first differential signal line Ga and the wiring of the second differential signal line 12 from the first electronic component Sa to the divided region Z (that is, the delay wiring body 10). The path lengths of the first differential signal lines Ga and the path lengths of the second differential signal lines 12 from the divided region Z (delay wiring body 10) to the second electronic component Sb are equal to each other. Are equal to each other.

  Therefore, from the first electronic component Sa to the first differential signal line Ga and the second electronic component Sb via the first delay wiring path 11 of the delay wiring body 10 and the first differential signal line Ga. Through the first electronic component Sa to the second differential signal line Gb, the second delay wiring path 12 of the delay wiring body 10 and the second differential signal line Gb. The total wiring path length up to the second electronic component Sb is equal to each other.

  By adopting such a configuration, for example, the first differential signal line Ga is a P-channel wiring, and the second differential signal line Gb is an N-channel wiring. An H signal is sent from Sa to the first differential signal line Ga, and an L signal is sent to the second differential signal line Gb.

Thereafter, an L signal is sent from the first electronic component Sa to the first differential signal line Ga, and an H signal is sent to the second differential signal line Gb. Further, an H signal is sent from the first electronic component Sa to the first differential signal line Ga, and an L signal is sent to the second differential signal line Gb.
The L signal and the H signal sent alternately are respectively transmitted through the first differential signal line Ga and the first delay wiring path 11 and the second differential signal line Gb and the second delay wiring path 12. The second electronic component Sb which is the electronic component on the receiver side is sent.

In the second electronic component Sb, the H signal and the L signal are alternately received from the two differential signal lines Ga and Gb and the first and second delay wiring lines 11 and 12, and the potential difference between the transmitted signals is determined. Then, the data is identified and, for example, an LSI logic circuit is operated to perform signal processing.
As described above, there is a portion where the wiring lengths of the differential signal lines Ga and Gb are different in the middle portion of the differential signal line pair G from the first electronic component Sa to the second electronic component Sb. However, by providing the delay wiring body 10 there, the difference in wiring path length between the first and second differential signal lines Ga and Gb is absorbed, so that the wiring path lengths are equal to each other.

  Therefore, the phase velocities (Vg [m / s]), which are phase amounts advanced per unit time of the signal, determined by the physical property value of the wiring board 1 and the line width are the same. The L signal and the H signal are alternately led from the first electronic component Sa through the differential signal line pair G and the delay wiring body 10 to the second electronic component Sb without any skew to obtain a clear waveform. Thus, the data transmission quality can be improved.

Hereinafter, a more specific configuration will be described.
FIGS. 2A and 2B are a perspective view of a part of the substrate wiring device and an exploded perspective view of the substrate wiring device in the first example according to the first embodiment.
Here, the first electronic component Sa and the second electronic component Sb are omitted, but they are assumed to be mounted as described above with reference to FIGS. A differential signal line pair G composed of a first differential signal line Ga and a second differential signal line Gb is connected from the first electronic component Sa to the second electronic component Sb.

  A dividing region Z is formed in the middle portion of the differential signal line pair G, the line direction of the differential signal line pair G from the first electronic component Sa to the dividing region Z, and the dividing region Z The line direction of the differential signal line pair G up to the second electronic component Sb is different and intersects at right angles. The delay wiring body 10 </ b> A is fitted into the dividing region Z and mounted on the wiring board 1.

The delay wiring body 10A is a block body having a predetermined plate thickness and having a rectangular shape in plan view. The delay wiring body 10A is provided with a first delay wiring path 11a and a second delay wiring path 12a described later.
That is, one connection part g1, h1 of the first delay wiring path 11a and the second delay wiring path 12a is provided on the side surface m1 of the delay wiring body 10A facing the first electronic component Sa. Further, the other connection portions g2 and h2 of the first delay wiring path 11a and the second delay wiring path 12a are provided on the other side surface m2 of the delay wiring body 10A facing the second electronic component Sb.

  Although the specific structure of each of the connection portions g1, g2, h1, and h2 is not particularly illustrated, a tongue piece protruding outward from the side surface of the delay wiring body 10A may be used. Therefore, both connection parts g1 and g2 of the first delay wiring path 11a are reliably connected to the divided end of the first differential signal line Ga. Both connection portions h1 and h2 of the second delay wiring path 12a are securely connected to the divided end portion of the second differential signal line Gb.

In the delay wiring body 10A, the connection portions g1 and g2 of the first delay wiring path 11a are provided on the main surface m3 which is a mounting surface on the wiring board 1, and here, before the separation. The bent portion K is formed in the same right-angle shape as the outer differential signal line.
In other words, the first delay wiring path 11a extends from the one connection portion g1 along the line direction of the first differential signal line Ga connected to the first electronic component Sa on the main surface m3. . In the middle part, it is bent along the line direction of the first differential signal line Ga connected to the second electronic component Sb and reaches the other connection part g2.

  On the other hand, the second delay wiring path 12a extends from the connection portion h1 directly above the side surface m1 to the main surface m4 facing the main surface m3. The main surface m4 is bent at the same right angle as the inner differential signal line forming the bent portion K before being divided. Furthermore, it traverses right below the side surface m2 and reaches the connecting portion h2.

  In this way, the first delay wiring path 11a provided in the delay wiring body 10A has a wiring path length that is only bent and formed only on one main surface m3. On the other hand, the second delay wiring path 12a has a total wiring path length of a portion provided on two side surfaces m1 and m2 which are 90 ° and a portion formed to bend on the other main surface m4. is there.

Therefore, even though the second delay wiring path 12a is the inner wiring of the first delay wiring path 11a, the wiring length of the second delay wiring path 12a is the wiring of the first delay wiring path 11a. It is the same as the road length.
In the wiring board device having the above configuration, for example, the first differential signal line Ga is a P-channel wiring, and the second differential signal line Gb is an N-channel wiring. The H signal and the L signal are sent simultaneously from the component Sa to the second electronic component Sb which is the electronic component on the receiver side, and then alternately and simultaneously.

In the second electronic component Sb, the H signal and the L signal are alternately received from the two differential signal lines Ga and Gb and the two delay wiring paths 11a and 12a. Then, data is identified by the potential difference of the transmitted signal, and signal processing is performed by operating, for example, an LSI logic circuit.
Even if there is a portion where the wiring path length of the differential signal line pair G is originally different from the first electronic component Sa to the second electronic component Sb, the wiring path can be provided by providing the delay wiring body 10A. Differences in length can be absorbed, skew that is a difference in signal propagation delay time is eliminated, the balance of the differential signal line pair G is minimized, and signal transmission quality can be improved.

FIG. 3 is a perspective view of a part of the substrate wiring apparatus of the second example according to the first embodiment.
Here, the first electronic component Sa, the second electronic component Sb, and the wiring board 1 are omitted, but the first electronic component Sa and the second electronic component Sb are first shown in FIG. It is mounted at the position explained in.

  A differential signal line pair G including a first differential signal line Ga and a second differential signal line Gb is connected from the first electronic component Sa to the second electronic component Sb. A dividing region Z is formed in the middle portion of the differential signal line pair G, the line direction of the differential signal line pair G from the first electronic component Sa to the dividing region Z, and the second region from the dividing region Z. The line direction of the differential signal line pair G up to the electronic component Sb intersects at right angles.

The delay wiring body 10 </ b> B is fitted to the dividing region Z and mounted on the wiring board 1. The delay wiring body 10B is a block body in which a plurality (three in this case) of delay wiring layers having a predetermined plate thickness and having a rectangular shape in plan view are stacked and integrated with each other.
The lowermost delay wiring layer directly mounted on the wiring board 1 is called “first delay wiring layer 10b1”, the middle delay wiring layer is called “second delay wiring layer 10b2”, and the uppermost delay wiring layer is called delay. The wiring layer is referred to as “third delay wiring layer 10b3”.

As described above, the first delay wiring path 10b1, the second delay wiring layer 10b2, and the third delay wiring layer 10b3 are laminated and integrated into the delay wiring body 10B. Delay wiring path 12b is provided.
That is, one connection part g1, h1 of the first delay wiring path 11b and the second delay wiring path 12b is provided on the side surface m1 of the first delay wiring layer 10b1 facing the first electronic component Sa. Further, the other connection portions g2 and h2 of the first delay wiring path 11b and the second delay wiring path 12b are provided on the other side surface m2 of the first delay wiring layer 10b1 facing the second electronic component Sb. .

  The first delay wiring path 11b traverses the first delay wiring layer 10b1 right above the side surface of the first delay wiring layer 10b1 from one connecting portion g1 and faces the main surface (upper surface) m5 that is mounted on the wiring board 1. Is bent. The bent shape is exactly the same right angle as the outer wiring of the bent portion K before being divided. The main surface m5 is crossed directly below the side surface m2 and reaches the other connection portion g2.

  The second delay wiring path 12b crosses the first delay wiring layer 10b1 and the second delay wiring layer 10b2 directly above the side surface m1 from one connection portion h1, and passes through the second delay wiring layer 10b2. The main surface (upper surface) m6 is bent. The bent shape is exactly the same as the inner wiring of the bent portion K before being divided. From the main surface m6, the second delay wiring layer 10b2 and the first delay wiring layer 10b1 are respectively crossed directly below the side surfaces m2 to reach the other connection portion h2.

  The difference from the example shown in FIG. 2 is that a plurality of (three) delay wiring layers 10b1 to 10b3 are overlapped to form the delay wiring body 10B, and the first delay wiring path 11b and the second delay wiring are formed. Both of the paths 12b are formed on different side surfaces m1 and m2 of the first delay wiring layer 10b1 and the second delay wiring layer 10b2.

  As a result, the first delay wiring path 10b1 and the second delay wiring path 10b2 are both exposed to the side surface of the delay wiring body 10B, and have the same effects as the example shown in FIG. It is easy to check the connection position and connection state of g1, g2 and the first differential signal line Ga with respect to the divided end portion, and to the divided end portions of the connection portions h1, h2 and the second differential signal line Gb. It is easy to check the connection position and connection state, and workability can be improved.

  The third delay wiring layer 10b3 is not provided with the first and second delay wiring paths 10b1 and 10b2. However, the first and second delay wiring paths 10b1 and 10b2 and the first and second delay wiring paths 10b1 and 10b2 are not provided. This is advantageous in that it has the function of a cover that covers the delay wiring layers 10b1 and 10b2 and prevents electrical accidents.

  Although the bent portion of the first delay wiring path 11b is formed on the upper surface m5 of the first delay wiring layer 10b1, it may be provided on the lower surface of the second delay wiring layer 10b2. Further, although the bent portion of the second delay wiring path 12b is provided on the upper surface of the second delay wiring layer 10b2, it may be provided on the lower surface of the third delay wiring layer 10b3.

  FIG. 4 is a perspective view showing a part of the wiring board device of the third example according to the first embodiment. Although the first electronic component Sa, the second electronic component Sb, and the wiring board 1 are omitted, here, the first electronic component Sa and the second electronic component Sb are in the same position with respect to the wiring board 1. Has been implemented.

  A differential signal line pair G, which is two differential signal lines including a first differential signal line Ga and a second differential signal line Gb, from the first electronic component Sa to the second electronic component Sb. Is connected. A dividing region Z is formed in the middle portion of the differential signal line pair G, the line direction of the differential signal line pair G from the first electronic component Sa to the dividing region Z, and the second region from the dividing region Z. The line directions of the differential signal line pair G up to the electronic component Sb are parallel to each other.

The delay wiring body 10 </ b> C is fitted into the dividing region Z and mounted on the wiring board 1. The delay wiring body 10C is a block body having a predetermined plate thickness and having a rectangular shape in plan view, and is provided with a first delay wiring path 11c and a second delay wiring path 12c described later.
That is, one connection portion g1, h1 of the first delay wiring path 11c and the second delay wiring path 12c is provided on one side surface m1 of the delay wiring body 10C and on one end side in the width direction. The other connection portions g2 and h2 of the first delay wiring path 11c and the second delay wiring path 12c are provided on the same side surface m1 and on the other end side in the width direction.

  In the delay wiring body 10C, the connection portions g1 and g2 of the first delay wiring path 11c are provided on the main surface m3 of the delay wiring body 10C mounted on the wiring board 1. In other words, the first delay wiring path 11c is extended from the respective connection portions g1 and g2 along the line direction of the first differential signal line Ga, and the extended end portions are connected to each other at a predetermined portion. The main surface m3 is formed in a substantially U shape.

  The connection portions h1 and h2 of the second delay wiring path 12c are provided across the main surface m4 that crosses the side surface m1 directly above and further faces the main surface m3. Each of the connection portions h1 and h2 extends along the line direction of the second differential signal line Gb, and the extended end portions are connected to each other at a predetermined portion. That is, the second delay wiring path 12c is provided twice on the side surface m1, and is formed in a substantially U shape on the main surface m4.

  Since the second delay wiring path 12c is formed inside the first delay wiring path 11c, comparing only the substantially U-shape on the main surface m3 and the main surface m4, the wiring of the second delay wiring path 12c The path length is shorter than the wiring path length of the first delay wiring path 11c. However, the second delay wiring path 12c crosses the side surface m1 twice, and the wiring path length corresponding to the second delay wiring path 12c is added.

  That is, the lengths of the first delay wiring path 11c and the second delay wiring path 12c are the same, and therefore, the first electronic component Sa reaches the second electronic component Sb via the delay wiring body 10C. The total wiring path lengths of the first differential signal line Ga and the second differential signal line Gb are the same.

  As a result, the same operational effects as the example described above are obtained. In addition, a differential signal line pair G may be formed in a U-turn at a predetermined portion in the wiring pattern layout for the electronic component mounted on the wiring board 1. Therefore, as described above, the differential signal line pair G in the U-turn portion is divided, and the delay wiring body 10C is provided in the division region Z.

  The first delay wiring path 11c and the second delay wiring path 12c provided in the delay wiring body 10C are formed in a shape that bends 180 ° by forming two portions bent at 90 °, that is, a U-turn shape. The same effect as that of the wiring board having a portion bent at 90 ° can be obtained.

Next, it is 2nd Embodiment in this invention, Comprising: The 1st Example is demonstrated based on FIG. 5 (A) (B).
FIG. 5A is a perspective view of the delay adjusting body 10D. The delay adjusting body 10D is made of, for example, a synthetic resin material or a ceramic material, has a predetermined thickness, and is formed into a block body having a rectangular shape in plan view.

  A counterbore 15a having a substantially L shape in plan view is provided in the thickness direction from the upper surface to the lower surface in the figure, which is one main surface m8, and within the thickness range. When using such a delay wiring body 10D, the upper and lower surfaces are reversed from the state shown in FIG. 5A, and the main surface m8 on which the spot facings 15a are provided is the lower surface side.

FIG. 5B is a perspective view of a delay wiring body 10D mounted on the wiring board 1, which is a part of the wiring board device. Although the first electronic component Sa and the second electronic component Sb are omitted, they are mounted as described above with reference to FIGS.
A differential signal line pair G including a first differential signal line Ga and a second differential signal line Gb is wired from the first electronic component Sa to the second electronic component Sb. In view of the layout of the wiring pattern on the wiring board 1, a bent portion K is provided in the middle portion of the differential signal line pair G. As they are, the wiring path lengths of the first differential signal line Ga and the second differential signal line Gb are different from each other.

The delay adjusting body 10D is mounted on the wiring board 1 so that the upper and lower surfaces are reversed from the state shown in FIG. Specifically, the lower surface (main surface G8) of the delay wiring body 10D is placed on the bent portion K formed on the wiring board 1 in an inverted state.
And the counterbore part 15a provided in the delay wiring body 10D is made to follow the 1st differential signal line Ga which is an outer side wiring. Since the flat surface 15b other than the spot facing portion 15a is in close contact with the second differential signal line Gb which is the inner wiring, the flat surface 15b of the delay adjusting body 10D is in close contact. The spot facing portion is referred to as a “first facing portion 15a”, and the flat surface is referred to as a “second facing portion 15b”.

  In the bent portion K, the first differential signal line Ga having a long wiring path length, which is the outer wiring, is covered with the first facing portion 15a. The distance to the part 15a is large. Therefore, the first differential signal line Ga is exposed to an air layer that fills the first facing portion 15a.

  On the other hand, in the bent portion K, the second differential signal line Gb having a short wiring path length which is the inner wiring is connected to the second differential signal line Gb from the point where the second facing portion 15b is in close contact. The distance from the second facing portion 15b is zero (short). Therefore, the second differential signal line Gb is covered with the delay wiring body 10D itself.

  As described above, the propagation time t of the signal propagating to the differential signal lines Ga and Gb connecting the two electronic components Sa and Sb is the phase velocity Vg with respect to the wiring path length of the differential signal lines Ga and Gb. It is determined from the ratio of (m / s). The phase velocity is a phase amount that advances per unit time, and is determined by the physical property value of the wiring board and the line width of the wiring.

  A physical property value of a wiring board is affected by a dielectric constant of a member constituting the wiring board. Even if the wiring path lengths of the pair of differential signal lines are the same, the propagation time of the signal guided to the differential signal line of the wiring board composed of the (large) member having a high dielectric constant is the dielectric constant. It becomes longer (larger) than the propagation time of the signal guided to the differential signal line of the wiring board composed of the low (small) member.

  In the configuration of FIG. 5, both the first differential signal line Ga and the second differential signal line Gb are provided on the wiring board 1 made of a member having a dielectric constant of 4, for example, a ceramic material or a synthetic resin material. The delay wiring body 10D is also formed of a member having a dielectric constant of 4. Air has a dielectric constant of 1.

  In the bent portion K, the first differential signal line Ga is covered with the delay wiring body 10D having a dielectric constant of 4, but actually, the first opposing portion 15a faces and is exposed to the air having a dielectric constant of 1 that is filled. It is. On the other hand, the second opposing portion 15b, which is the delay wiring body 10D itself having a dielectric constant of 4, is in close contact with the second differential signal line Gb.

  Therefore, at the bent portion K, the dielectric constant of the portion of the wiring board 1 where the second differential signal line Gb is provided is smaller than the dielectric constant of the portion of the wiring board 1 where the first differential signal line Ga is provided. Become. Due to such a dielectric constant relationship, the apparent wiring path length on the first differential signal line Ga side is shortened.

  Therefore, the phase speed of the signal transmitted to the first differential signal line Ga is lowered, and the signal propagation time is shortened. The propagation time of the signal guided to the first differential signal line Ga that is the outer wiring is the same as the propagation time of the signal guided to the second differential signal line Gb that is the inner wiring, and there is no occurrence of skew. .

Next, a second embodiment of the present invention will be described with reference to FIG.
FIG. 6 is a perspective view of a part of the wiring board device. Although the first electronic component Sa and the second electronic component Sb are omitted, they are mounted as described above with reference to FIGS.

  A differential signal line pair G including a first differential signal line Ga and a second differential signal line Gb is wired from the first electronic component Sa to the second electronic component Sb. Here, only the second differential signal line Gb, which is an inner wiring, has a bent portion K in the middle, and the first differential signal line Ga, which is an outer wiring, is a divided region Z.

  Both ends of the delay adjuster 10E are connected to the divided portions of the first differential signal line Ga, and aerial wiring is provided between the ends. The aerial wiring has a bent shape substantially the same as the bent portion K of the first differential signal line Ga. That is, between both end portions of the delay wiring body 10E is a facing portion where the distance to the wiring board 1 is infinitely opposed.

  On the other hand, the second differential signal line Gb having a short wiring path length has the second differential signal line Gb itself also used as the delay adjusting body 10E, and the distance from the wiring board 1 is zero. Will be provided.

Since the aerial wiring of the delay wiring body 10E is spaced from the wiring pattern forming surface of the wiring board 1, an air layer is formed between the delay wiring body 10E and the wiring board 1 surface. Therefore, the delay wiring body 10E is affected by an air layer having a dielectric constant of 1.
On the other hand, since the second differential signal line Gb that also serves as a part of the delay wiring body 10E is formed on the wiring board 1 over the entire length, it is influenced by, for example, the wiring board 1 member having a dielectric constant of 4. . At the bent portion K, the first differential signal line Ga has a low dielectric constant, and the second differential signal line Gb has a high dielectric constant while maintaining the physical properties of the wiring board 1.

  By reducing the dielectric constant of the first differential signal line Ga, the signal phase speed is lowered, the signal propagation time is shortened, and the apparent wiring path length is shortened. Therefore, the wiring path length of the first differential signal line Ga is considered to be the same as the wiring path length of the second differential signal line Gb, and the signals guided to the mutual differential signal lines Ga and Gb. Propagation time is the same and no skew occurs.

Next, a third embodiment of the present invention will be described with reference to FIG.
FIG. 7 is an exploded perspective view of a part of the wiring board device. Although the first electronic component Sa and the second electronic component Sb are omitted, they are mounted as described above with reference to FIGS.
The wiring substrate 1A is composed of a plurality (two in this case) of laminated substrates 1a and 1b laminated together, and is integrated in a laminated state. The first electronic component Sa and the second electronic component Sb are mounted on the first laminated substrate 1a on the upper side.

A bent portion K is provided in the first differential signal line Ga and the second differential signal line Gb. The first differential signal line Ga is formed over the entire length including the bent portion K on one main surface (upper surface in the drawing) m10 of the first laminated substrate 1a.
In the second differential signal line Gb, only the bent portion K is provided on one main surface m10 of the first multilayer substrate 1a. Both ends of the bent portion K are interrupted portions Ya that are interrupted at a predetermined interval. The first electronic component Sa and the second electronic component Sb are provided on the same main surface m10 from the interrupted portion Ya. It is done.

Both ends of the interrupting portion Ya in the first multilayer substrate 1a pass through the plate thickness of the multilayer substrate 1a as they are, and project to a main surface (lower surface in the figure) m11 facing the main surface m10. These penetrating portions may be replaced with through holes.
One main surface (upper surface in the figure) m12 of the lower layered substrate 1b is provided with an interruption corresponding part Yb which is a wiring pattern corresponding to the interruption part Ya in the first laminated substrate 1a. It connects with the penetration part provided in 1a.

  Here, the second differential signal line Gb includes four through portions provided in the first multilayer substrate 1a and two interruption corresponding portions Yb provided in the second multilayer substrate 1b. A detour part Y is provided. As described in FIG. 1, the total length of the detour portion Y is the difference between the wiring path length of the first differential signal line Ga and the wiring path length of the second differential signal line Gb in the bent portion K. It corresponds to.

  In other words, the second differential signal line Gb having a portion with a short wiring path length includes a detour portion Y having the same wiring path length as the first differential signal line Ga having a longer wiring path length. ing. Since the wiring path lengths of the differential signal lines Ga and Gb are the same, the propagation times of signals guided to the differential signal lines Ga and Gb are the same, and no skew is generated.

  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 combinations of a plurality of constituent elements disclosed in the above-described embodiments.

The figure explaining the basic composition of the wiring board device of the present invention. The perspective view of a part of board wiring device of the 1st example concerning the 1st embodiment in the present invention, and the exploded perspective view of a part of board wiring device. The perspective view of a part of board wiring device of the 2nd example concerning the embodiment. The perspective view of a part of board wiring device of the 3rd example concerning the embodiment. The perspective view of the delay adjustment body of 1st Example based on 2nd Embodiment in this invention, and the perspective view of a part of board | substrate wiring apparatus. The perspective view of a part of board wiring device of the 2nd example concerning the embodiment. The perspective view of a part of board | substrate wiring apparatus based on 3rd Embodiment in this invention. The figure explaining a differential signal transmission system. The figure explaining the skew phenomenon at the time of employ | adopting a differential signal transmission system. The figure explaining the problem which arises by skew. The figure explaining the cause of skew.

Explanation of symbols

  Sa ... first electronic component, Sb ... second electronic component, 1 ... wiring board, Ga ... first differential signal line, Gb ... second differential signal line, G ... differential signal line pair, Z ... Dividing region, 10... Delay wiring body, 11... First delay wiring path, 12... Second delay wiring path, g 1, g 2, h 1 and h 2. 2 opposing parts, Y ... detour part.

Claims (7)

A wiring board on which a plurality of electronic components are mounted;
A differential signal line pair consisting of a pair of differential signal lines that are wired in parallel to each other on this wiring board and have a region divided in the middle,
A delay wiring body mounted on the divided region of the differential signal line pair in the wiring board;
The delay wiring body is connected to the respective ends of the pair of differential signal lines constituting the divided differential signal line pair, and the wiring path lengths are set to be the same. A wiring board device comprising a delay wiring path and a second delay wiring path. The differential signal line pair is:
The differential signal line pairs of one differential signal line pair wired up to the divided area and the other differential signal line pair wired from the divided area are in mutual line directions. Provided differently,
The delay wiring body is
On this one side, it is provided with a connecting portion for connecting with one differential signal line pair wired up to the divided region,
2. The wiring board device according to claim 1, further comprising a connection portion connected to the other differential signal line pair wired from the divided region on a surface different from the surface on which the connection portion is provided. The differential signal line pair is:
The differential signal line pairs of one differential signal line pair wired up to the divided area and the other differential signal line pair wired from the divided area are in mutual line directions. Provided in parallel,
On one surface of the delay wiring body, a connection portion connected to one differential signal line pair wired up to the divided region,
2. The connection portion connected to the other differential signal line pair wired from the divided region is provided on the same surface as the surface where the connection portion of the delay wiring body is provided. Wiring board device. A wiring board on which electronic components are mounted;
A differential signal line pair composed of a first differential signal line and a second differential signal line, which are wired in parallel to each other on this wiring board and in which a part having a different wiring path length is formed in the middle part;
Each of the first differential signal line and the second differential signal line, which are provided at different portions of the wiring path length of the differential signal line pair in the wiring board and constitute the differential signal line pair. A wiring board device comprising: a delay wiring body having opposing portions which are opposed to each other at different distances and having the same apparent wiring path length. The delay adjuster is
A first counter that opposes the differential signal line having a longer wiring path length, either the first differential signal line or the second differential signal line constituting the differential signal line pair, with a distance therebetween 5. The wiring board device according to claim 4, further comprising a second opposing portion that is in close contact with the differential signal line having a shorter wiring path length. The delay adjuster is
By dividing the differential signal line having the longer wiring path length and connecting the divided portions, an aerial wiring having a facing portion that makes the distance to the wiring board infinite,
5. The wiring board according to claim 4, wherein the differential signal line having a shorter wiring path length includes an opposing portion having a distance from the wiring board of zero, which also serves as the differential signal line itself. apparatus. A wiring board composed of a plurality of laminated boards stacked on top of each other, with electronic components mounted on the uppermost laminated board,
A differential signal line pair consisting of a pair of differential signal lines that are wired in parallel to each other on this wiring board and have different wiring path lengths;
Of the pair of differential signal lines constituting the differential signal line pair, the differential signal line having a portion with a short wiring path length has the same wiring path length as the differential signal line having the longer wiring path length. A wiring board device comprising a bypass portion across a plurality of laminated substrates so as to achieve this.

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