JP3397707B2 - Substrate with shield plane with various aperture patterns for transmission time and impedance control - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate or a flexible cable (flexible printed circuit board (FP
C), flexible flat cable (FFC), etc., and more particularly to a substrate having a shield plane or a flexible cable having various opening patterns for controlling impedance and transmission time.

[0002]

2. Description of the Related Art Microstrips are used for high-speed logic circuits in computers.
And stripline structures are very often used, which are especially used for internal interconnection between these circuits. Furthermore, in order to achieve high-speed data transmission, the differential mode of the transmission line with shield plane is necessary to reduce the transmission error caused by noise during data transmission at low voltage (3.3V). And it is an important method. A transmission line differential mode requires an impedance of 100 ohms. Recently, automation techniques and equipment have made it possible to build structures with controllable impedance and transmission timing in the signal path. However, the asymmetric structure of microstrip is
It has the drawback of greatly impairing the mechanical properties of flexible cables and it has also allowed stringent levels of extraneous electromagnetic radiation.

The symmetrical structure of the stripline is the FFC.
It has the effect of improving the mechanical properties of the (flat flexible cable) such as flexibility and anti-fatigue property and greatly reducing the effect of electromagnetic radiation. However, due to the additional ground reference plane due to the symmetrical structure of the strip line, the impedance of the signal path is significantly reduced by increasing the capacitance between the signal line and the additional ground reference plane. Considering the high flexibility and anti-fatigue property of the strip line type FFC against repeated operation, the distance between the signal line and the ground reference plane must be shorter than the distance between the pair of differential mode signal lines. At the same time, this also suggests that it is necessary to prevent an increase in the thickness of the printed circuit board and maintain a desired impedance for the printed circuit board by a similar design method.

The ground plane or other voltage reference plane lies in a plane parallel to the conductor plane, and the conductor is designed flat on the flexible cable or printed circuit board. Its purpose is to control the impedance of conductors and to block the transmission of electromagnetic radiation from conductors carrying high frequency signals. The solid ground plane is usually used for a printed circuit board or a flexible cable, but it has no flexibility except for the thin film type.

Another drawback of the solid ground plane is that the impedance of the signal line is lower than desired, which is due to the short distance between the signal line and the solid ground plane or reference plane. Because a large capacitance is formed. However, if an attempt is made to increase the impedance of the signal line by increasing the distance between the signal line and the solid ground plane or the reference plane, the thickness is increased and thus the flexibility is impaired, and it is easily broken by repeated operation. . Similarly, the thicker the printed circuit board becomes, the heavier the manufacturing cost becomes.

Reference planes having conductor elements formed in a grid have been implemented in microstrip designs to increase impedance and provide flexibility. However, it has been found that it is extremely difficult to control both the signal line impedance and the transmission timing by a grating reference plane having only a single pattern, since the grating is not continuous like the solid reference plane.

One of the problems in impedance control of flexible cables and printed circuit boards that employ a grid reference plane, especially stripline type cables, is the turn structure. Normally, if a change in the direction of the signal line is required, such as a 90 ° turn, this turn will not be incorporated into the signal line with a single 90 ° bend angle. Rather, the change of direction is usually implemented as a signal line that continuously changes from the original direction to the new direction. The signal lines appear to have different alignments in the conduction of the upper and lower bridges with the gratings located at various points at their turn portions.
Such alignment results in impedance diversity at each point, effectively causing impedance discontinuities.

The impedance of microstrip and stripline structures is determined by the width of the signal conductor, the distance of the conductor from the reference plane, the insulator surrounding the conductor, and the thickness of the conductor. However, such well-known stripline and microstrip structure impedance determination methods place many constraints on the designer. For example, double impedance of 100 ohms is required for differential mode transmission lines. Obtaining such high impedances using existing technology requires increasing the distance between the signal conductor and the reference plane. However, this requires a thicker flexible cable, and as the thickness of the flexible cable increases, its flexibility and fatigue resistance decrease. And coating conductors with different insulating materials,
Alternatively, it is necessary to use an expensive printed circuit board having a nonstandard thickness. Such non-standard printed circuit boards are not only expensive, but also unsuitable for many applications due to their thickness.

There is a drawback in the traditional microstrip structure with high transmission rates, which causes crosstalk in both the front and back directions, which severely degrades the signal quality. Crosstalk is the effect of coupling signals from one channel to another. There are several causes of crosstalk, one of which is the imbalance of cable parameters, especially capacitance and inductance between conductors. This imbalance causes severe coupling of signals from one conductor to another. And such imbalances are typically exacerbated in traditional microstrip structures when conductors are exposed to non-uniform media.

Solid surface conductors in traditional microstrip structures tend to generate high levels of electromagnetic radiation that interfere with the functioning of peripheral electronic devices. This intense radiation also affects the manipulation of surface conductors. In traditional microstrip structures with high transmission rates, it is difficult to provide a suitable shield because the conductor surface is free to radiate into the holes of the system encapsulating the substrate. This indicates that there is a need to reduce such radiation containment in stripline structures. But,
In order to implement the desired high impedance conductor in a stripline structure, it was necessary to take the undesirable approach of drastically increasing the distance between the reference plane and the conductor. Such an undesired increase in thickness also poses a problem in the application to a notebook computer substrate and other standard substrates which require thinness and cost reduction.

Since the stripline type flexible cable has a bending ability of thousands of times, the desired impedance and the transmission timing can be achieved, the signal can be transmitted without degrading the signal quality, and the acceptable shielding ability can be provided. In order to do so, a flexible reference plane is needed.

Due to the slow wave effect, the transmission time on the solid plane is faster than that of a shield with an aperture pattern. If the difference in the length of the transmission line is enough to have the timing effect for the high transmission rate, according to the traditional method, in some place to compensate for this effect an extra equivalent length to a short transmission line. Add However, this traditional method of compensating for extra length induces unwanted electromagnetic radiation due to impedance discontinuities.

Even when the transmission lines have the same length, sometimes transmission timing control is necessary to avoid the important harmonic mode of high transmission rate. The transmission time is related to the induction constant of the coating material, the slow wave effect due to the shield pattern, and the matching length of the transmission line. If it equates to the significant harmonic mode of high rate transmission, the harmonic mode of this signal will bounce back and forth between the two ends of the transmission line, compromising signal transmission.

[0014]

The present invention relates to a flexible printed circuit board (preferably a low voltage differential transmission mode circuit) having a shield plane for a transmission line, or a flexible cable. According to the invention, both the impedance and the transmission time of the transmission line of the cable can be controlled by the shield plane with various empty aperture patterns. The capacitance and slow wave effect related to the combination of the opening patterns, and the arrangement shape related to the position of the opening pattern are the main factors to be considered.

The various opening patterns are mainly classified into two types. The first category is a shield plane design with a set of aperture patterns, and the second category is a set of aperture patterns (preferably a fixed aperture pattern) and a gradually diversified set of small solid patterns. Is a combination of.

It is also intended to design the transmission time and impedance in consideration of the mechanical flexibility of the flexible cable or the thickness of the printed circuit board.

Various aperture patterns are operated on the shield plane, thereby generating the slow wave effect of the transmission line and reducing the capacitance of the transmission line, thereby controlling the transmission time and increasing the impedance as necessary.

A thin film type conductive element, such as silver braze, on the shield plane is connected and designated as the only ground path for the transmission line. A matching resistive type impedance is provided to reduce the unwanted harmonic mode effects bouncing back and forth at the two ends of the transmission line. At least one (preferably one) ground path for the DC power supply is added to reduce the power consumption of the silver solder. The turn portion of the cable is provided with a structure that blocks crosstalk between transmission lines.

Therefore, the object of the present invention is to provide a kind of printed circuit board or flexible cable, which has a first shield plane, which has a predetermined shield shape and is conductive. An element, the conductive element having a first set of aperture patterns and a first predetermined configuration. This predetermined arrangement shape is related to the arrangement of the opening patterns. There are two predetermined layouts, one not related to the curve of the signal line and the other related to the curve of the signal line. The printed circuit board and the flexible cable further have a second shield plane, which has a predetermined second opening pattern set and a second predetermined arrangement shape.

Another object of the present invention is to provide a method for simplifying the design of impedance and transmission time according to the first and second arrangement shapes. In that way,
The same opening pattern set and the same arrangement shape are used, but the first shield plane is a mirror image of the second shield plane. The same shield plane is used to further simplify impedance and transit time design. A conductive element is disposed between the first and second shield planes to form a signal conductor.

On the other hand, the object of the present invention is to provide a printed circuit board or a flexible cable including a first shield plane having a predetermined shield shape, which is one fixed opening pattern (or set of opening patterns) and It is intended to include a conducting element with a combination of predetermined subdivisions of a gradually diversifying solid pattern.
Printed circuit board or flexible cable is second
And a second shield plane having a second predetermined shape. A conductive element is disposed between the first and second shield planes to provide a signal conductor.

The present invention further provides a method of selecting a wide variety of aperture patterns, thereby inducing a slow wave effect to compensate for this timing effect and reduce electromagnetic radiation.

Another object of the present invention is to provide a printed circuit board or flexible cable having a microstrip structure, which comprises a shield plane having a predetermined shield shape, the shield plane having a predetermined opening pattern and a predetermined shield pattern. The arrangement shape of

It is another object of the present invention to provide a printed circuit board or a flexible cable having a shield plane and having a microstrip structure, the shield plane having a predetermined shield shape, and the shield shape having one shield shape. It includes a conducting element with a combination of a fixed aperture pattern (or a set of various aperture patterns) and a predetermined subdivision of an increasingly diverse solid pattern.

[0025]

The invention according to claim 1 is a substrate
In the first predetermined shield shape,
Limited to a plane, the position of the first set of predetermined aperture patterns
A first set of predetermined apertures having a first predetermined arrangement shape including
And pattern, of the predetermined disposed in a predetermined position the first set of source
The first predetermined seat including a combination with a lid pattern.
The second predetermined shield shape and the second
Position of the second set of predetermined aperture patterns, limited to the plane of
A second set of predetermined openings having a second predetermined configuration including
Mouth pattern and a predetermined second set of predetermined positions
The above-mentioned second predetermined pattern including a combination with a solid pattern.
And a signal-conducting element.
A pair of differential modes arranged between the plane and the second plane
Signal conduction element limited to the middle of the signal conduction element of
Virtual pair of differential-mode signal-conducting elements
With a signal-conducting element with a ground
The signal conducting element or the virtual ground is the first and second
And the second predetermined shield shape at each predetermined position
The substrate is characterized by being arranged. Claim
According to a second aspect of the present invention, in the substrate according to the first aspect, the opening pattern is provided.
The maximum size of the signal transmission is
A base characterized by being smaller than 1/20 wavelength of the frequency
It is a plate. The invention of claim 3 is based on the substrate of claim 1.
And the first and second predetermined arrangement shapes are grids.
The substrate is characterized by The invention of claim 4 is
The substrate according to claim 1, wherein the first and second predetermined arrangement types are provided.
The direction of the signal conducting element or a pair of differential models.
The virtual ground of the signal-conducting element of the
The substrate is characterized by The invention of claim 5 is
The substrate according to claim 1, wherein the predetermined opening pattern is circular.
The substrate is characterized by being processed. Claim 6
The invention provides a substrate according to claim 1, wherein a predetermined opening pattern is provided.
Is an ellipse, which is a substrate.
According to a seventh aspect of the invention, in the substrate of the first aspect, a predetermined opening is provided.
As a substrate, characterized in that the mouth pattern is rectangular
ing. The invention of claim 8 is the substrate of claim 1, wherein
The predetermined opening pattern is a rhombus ,
It is used as a substrate. The invention of claim 9 provides the substrate of claim 1
At the predetermined position of the solid pattern,
The part that needs to be bent, or both ends of the signal conducting element
The substrate is characterized by being processed. Claim 10
According to the invention of claim 1, in the substrate of claim 1,
The mouth pattern and signal conducting element are flexible
The substrate is characterized by including a bull. Claim
An eleventh aspect of the present invention is the substrate according to the first aspect, further comprising:
Planes are connected to form a pair of differential mode signal-conducting elements.
The power ground, power supply, power supply ground
Or, the normal mode signal is
The circuit board is characterized by being transmitted. Claim
A twelfth aspect of the invention is the substrate according to the first aspect, wherein the opening pattern is provided.
As a substrate, characterized by a symmetrical pattern
There is. The invention according to claim 13 is the substrate according to claim 12,
And a virtual graph of a pair of differential mode signal conducting elements.
The opening pattern of the conductor or signal conducting element is symmetric
The base is characterized by being determined in the center of the opening pattern.
It is a plate. The invention of claim 14 provides the substrate of claim 1
The first and second predetermined shield shapes are
Characterized by including a conducting element with an opening pattern
And the substrate. The invention of claim 15 is the claim
14 substrates, the first and second sets of predetermined opening patterns
Combination of turns, first and second plane conductive elements
Space is aligned on the line for each conducting element
And the aperture pattern is the impedance for the signal conducting element.
Matches impedance, transmission timing and electromagnetic emission control
It is designed as a substrate.
According to a sixteenth aspect of the present invention, in the substrate of the fourteenth aspect, the first aspect is provided.
And the second plane conductive element is a thin film type conductive element.
It is used as a substrate. Contract
The invention of claim 17 provides the first and second aspects of the substrate of claim 14.
And the second shield shape has a predetermined opening pattern.
The second predetermined configuration includes an offset element including a conducting element.
The same as the first predetermined layout shape
The substrate is a feature. The invention of claim 18 is a contract
In the substrate of Requirement 17, the maximum size of the opening pattern is
The highest frequency wave of the signal transmitted to the signal conducting element
As a substrate characterized by being less than 1/20 of the length
There is. The invention of claim 19 is based on the substrate of claim 17.
A combination of predetermined opening patterns of the first set and the second set,
The space of the conducting elements in the first and second planes is
Aligned in line with the conducting element, the opening pattern is
Impedance, transmission tie for signal conducting elements
And is designed to match
The substrate is characterized by Invention of Claim 20
Are the first and second predetermined values in the substrate of claim 17.
The arrangement shape is a lattice, and the predetermined offset is the signal conduction error.
1/2 of the grid space in the direction of the element
The substrates are characterized in that they are equal. Claim 21
The invention according to claim 17 provides the substrate according to claim 17,
Predetermined layout shape depends on the direction of each signal conducting element
The substrate is characterized by matching. Claim
The invention according to claim 22 is the substrate according to claim 17, wherein a predetermined opening is provided.
The mouth pattern is a symmetrical pattern,
It is used as a substrate. The invention of claim 23 is based on the invention of claim 17.
Make sure that the plate has a circular opening pattern.
The substrate is a feature. The invention of claim 24 is a contract
In the substrate of Requirement 17, the predetermined opening pattern is elliptical
The substrate is characterized in that Claim 2
According to a fifth aspect of the invention, in the substrate according to the seventeenth aspect, a predetermined opening pattern is provided.
It is used as a substrate, characterized in that the turns are rectangular.
It The invention of claim 26 is the substrate of claim 17,
The predetermined opening pattern is a rhombus,
It is used as a substrate. The invention of claim 27 is based on the invention of claim 17.
In the plate, the predetermined position of the solid pattern is the bent portion,
Both the part that needs to be bent or the signal conducting element
The substrate is characterized by being an edge. Claim
A twenty-eighth aspect of the present invention is the substrate according to the first predetermined shield type.
And limited to a first plane, a set of predetermined openings
A set of predetermined shapes with predetermined layout shapes including pattern positions
Opening pattern and a set of predetermined
Of the first predetermined, including a combination of solid patterns of
The shield shape and the signal conducting element, and the first
A pair of differential modes arranged in a second plane parallel to the plane of
A pair of differential modules defined in the middle of the signal
With a virtual ground for the signal-conducting elements of the
A signal-conducting element,
Or the virtual ground is related to the predetermined shield shape.
As a substrate, which is characterized by being placed in a fixed position
It The invention of claim 29 is the substrate of claim 28,
A substrate, characterized in that the predetermined arrangement shape is a lattice
I am trying. The invention of claim 30 is the substrate of claim 25.
In addition, the predetermined arrangement shape is the signal conduction element
Virtual of a single or pair of differential mode signal conducting elements
As a substrate characterized by matching to ground
It The invention of claim 31 is the substrate of claim 28,
The predetermined opening pattern is circular,
It is used as a substrate. The invention of claim 32 is based on the invention of claim 28.
The predetermined opening pattern on the plate was elliptical
The substrate is characterized by. The invention of claim 33 is
The substrate according to claim 28, wherein the predetermined opening pattern is rectangular.
The substrate is characterized in that Claim 3
According to a fourth aspect of the present invention, in the substrate according to the twenty-eighth aspect, a predetermined opening pattern is provided.
As a substrate, characterized in that the turns are diamond-shaped
It The invention of claim 35 is the substrate of claim 28,
It is necessary to bend the solid pattern at a predetermined position and bend it.
Be sure that the required parts or both ends of the signal conducting element are
The substrate is characterized by Invention of Claim 36
Is a predetermined opening pattern in the substrate of claim 28.
As a substrate, characterized by having a symmetrical pattern
It The invention of claim 37 is the substrate of claim 36,
Virtual ground signal Den guiding elements of a pair of differential mode
Alternatively, the aperture of the signal conducting element has a symmetrical aperture pattern.
A substrate characterized by being determined in the center of the pattern and
is doing. The invention of claim 38 is based on the substrate of claim 28.
And the specified shield shape has a specified opening pattern.
As a substrate, characterized by including a conductive element
ing. The invention of claim 39 resides in the substrate of claim 38.
And the maximum dimension of a given aperture pattern is the signal conducting element.
From 1/20 of the wavelength of the highest frequency of the signal transmitted to
The substrate is characterized by its small size. Claim 40
The invention according to claim 38 provides a substrate according to claim 38, wherein a set of predetermined openings is provided.
Mouth pattern, line aligned with respect to signal conducting element
Space of the conducting element on the first plane and
The combination of lid patterns impinges on the signal conducting elements.
Required by impedance, transmission timing and electromagnetic radiation control
A board characterized by being designed to match
I am trying.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 is a plan view of a first embodiment of a shield substrate 30 according to the present invention.

The substrate 30 electrically connects the base of the notebook computer to the movable display with a high transmission rate (455 MHZ) and a high impedance (100 ohms) in a low voltage (3.3 volt) differential mode. . The curved substrate 30 has the effect of diversifying the transmission timing, and the substrate having the matching length (about 32 cm) provides the second harmonic mode 910 MHz with the transmission frequency of 455 MHz. The impedance is designed to be about 100 ohms. A time domain reflector (TDK) is used to measure the transmission timing with different aperture patterns, and the measured transmission time is 1.8n.
sec (for solid reference pattern) to 2.5n
It was in the range of sec (with respect to the lattice pattern).

Therefore, it is an object of the present invention to simultaneously control impedance and transmission timing by using shield planes with various aperture patterns. Various opening patterns are classified into the following two main categories. In the first class, a first predetermined opening pattern set is provided on the shield plane, and in the second class, a predetermined fixed opening pattern set (preferably one) and a predetermined small portion of a gradually diversifying solid pattern. A combination. The shape of these aperture patterns can control various slow wave effects as well as impedance to compensate for various timing effects and reduce unwanted electromagnetic radiation.

The substrate 30 belongs to the second class, and a small portion of the solid shield, which is gradually and diversified in a predetermined manner, is a region of a conductive element having no opening pattern, that is, a solid pattern, as shown in 4 part of FIG. It is said that The preferred placement of the solid pattern is at the turns of the substrate 30, at both ends of the cable, and where bending of the cable is required, because impedance discontinuities at these locations are usually unavoidable. The preferred opening pattern is symmetrical, for example circular, rectangular, elliptical or rhombic.
The most desirable of these is circular, which is symmetrical from any direction.

As shown in FIGS. 1 and 2, in the present invention, differential mode transmission lines 60, 62, 64, 66, 68, 70 are used.
Two shield planes 28, 40 are used as grounds for. The ground conductor connecting the both ends of the cable is not provided in the middle layer of the cable. Therefore, it is not necessary to provide an extra ground conductor in the middle layer between the two ends of the cable. Therefore, the present invention provides a mechanical property to withstand repeated bending and a design method capable of preventing electromagnetic radiation as compared with the traditional method. Further, in the present invention, the shield planes 28, 40 are used as the sole grounds for the differential mode transmission lines 60, 62, 64, 66, 68, 70 to obtain a better slow wave effect and to improve the transmission timing. Control. The transmission line 60, 62, 64, 6 is provided by providing a suitable resistance type impedance by using a thin film type conductive element.
The undesirable harmonic mode effect of bouncing back and forth between the two ends of 6, 68, 70 can be reduced.

In most cases, the DC power supply 88 is formed from one end to the other end of the substrate 30, as shown in FIG. 1, and is located substantially in the middle layer of the flexible substrate 30. Thin film type conductive element (ie silver solder)
Are high speed differential mode transmission lines 60, 62, 64, 6
Used only for grounding 6, 68, 70. Therefore, as shown in FIGS. 1 and 2, there is one path parallel to the differential mode transmission lines 60, 62, 64, 66, 68, 70 as the ground 54 of the DC power source 88 in the entire middle of the flexible substrate 30. Only. This ground 54 is designed only for the DC power source 88, and the transmission lines 60, 62, 6
Not for 4, 66, 68, 70. Then, as shown in FIGS. 1 and 2, the transmission lines 60, 62, 64, 6
It is arranged as far as possible from 6, 68 and 70.

The substrate 30 of the present invention, as shown in FIG. 2, includes a top shield plane 28 having conductive elements with a circular opening pattern 82 of a predetermined shape and a set of predetermined same openings. The lower shield plane 40 including the conductive element and the differential mode signal conductor (ie, the transmission line 6).
0, 62, 64, 66, 68, 70), the virtual grounds 80 of each pair of signal conductors are arranged in a line along the line connecting the centers of the opening patterns 82. The use of thin film type conductive elements with repeated bending and anti-fatigue mechanical properties, such as silver braze, is preferred for the conductive elements in both the upper and lower shield planes 28,40. The printed silver solder is then easy to implement the complex shield pattern required by the present invention.

The upper shield plane 28 is preferably aligned with the lower shield plane with respect to the center of the opening pattern 82 without offset. D2 is the spacing, where the virtual ground 80 of the differential mode transmission lines 68, 70 is the portion of the top shield plane 28 that has the conducting element. Conversely, D3 is the spacing and the actual ground 80 is the portion of the top shield plane 28 that has no conductive elements. Tested at many locations on the ground 80, a pair of differential mode transmission lines 68, 7
The slow wave effect was confirmed in the portion of No. 0 located inside the opening pattern. The slow wave effect depends on the bending of the signal conductor and the spacing by D1 and D2 shown in FIG. The preferred shape of the circular aperture pattern without redirection of the cable is D2 = D3. With respect to the substrate 30, the virtual ground 80 is located to the left of the center of the circle, which is optimal for the transmission lines 68, 70 to have equal timing, as the spacing D2 increases with respect to the transmission line 68. This is because the line 70 decreases.
Capacitance effects and slow wave effects on the opening patterns in the upper and lower shield planes 28, 40 are used to design the impedance of the flexible cable and the transit time from one end to the other.

The distance D1 is equal to the upper and lower shield planes 2.
When referring to a maximum aperture size of 8,40, D1 is preferably a transmission line 60,6 to effectively block electromagnetic radiation.
Designed to be less than 1/20 of the smallest expected wavelength dimension of the signal flowing through 2, 64, 66, 68, 70. This allows both the upper and lower shield planes 28, 40 to be effective shield planes.

In order to make the following description easier to understand, description will be given using XY and Z coordinates. Figure 2 shows the X and Y axes
It is on a horizontal plane as shown in. The upper and lower shield planes are parallel to the horizontal plane. Similarly, differential mode transmission lines 60, 62, 64, 66, 68, 70 lie between and parallel to the upper and lower shield planes 28, 40. As shown in FIGS. 1 and 2, the main directions of the differential mode transmission lines 60, 62, 64, 66, 68, 70 are parallel to the Y axis, or X when bent by 90 ° as required. Parallel to the axis. As shown in FIG. 3, the Z axis is perpendicular to the X and Y axes.

The arrangement shape of the opening pattern is as follows. The first one is related to the curve of the signal line and the second one is not related to the curve of the signal line. The cables 30, 130, 372 in FIGS. 1, 6, 17 belong to the first one.
And the cables 210 and 310 in FIGS. 9 and 14 belong to the second one.

FIG. 3 is a sectional view taken along line 3-3 of FIG. Solder masker layers on both sides protect the conductive elements. The structure shown in FIG. 3 is as follows. The first layer is a very thin solder masker layer. The second layer is an upper shield plane 28 having conductive elements, which is defined as a first plane with a first predetermined shield shape. The third layer is made of PI (polyamide), PET or equivalent flexible material.

The fourth layer is an adhesive layer. The fifth layer is a signal conductor (copper) layer. The sixth layer, the seventh layer, the eighth layer and the ninth layer are the same as the fourth layer, the third layer, the second layer and the first layer, respectively. The eighth layer is a bottom shield plane 40 with conductive elements, which is defined as a second plane with a second predetermined shield shape. The third and fourth layers can be combined with a special adhesive-type flexible material, which can reduce the thickness, as well as the sixth and seventh layers. According to the present invention, a 6 mil flexible cable can be manufactured.

FIG. 4 is an enlarged view of a portion indicated by reference numeral 4 in FIG. 1, showing a method of forming a 90 ° turn in the signal conductor.
The gradually diversifying solid patterns 72, 74 are arranged on the turn portion of the cable 30, and the solid patterns 72 are arranged on the upper shield plane 28 as shown in FIGS.
In addition, the solid pattern 74 is on the lower shield plane 74,
It is arranged. Via 5 at the turn of cable 30
0 is disposed, and the via 50 is disposed between the pair of transmission lines 64 and 66 and the other pair of transmission lines 68 and 70 to block crosstalk due to discontinuity at the turn portion. These vias are a pair of transmission lines 64 and 66 and another pair of transmission lines 6.
It is not necessary when there is a large gap between 8 and 70. This is because severe crosstalk does not occur when the two pairs of transmission lines are largely separated from each other. If an accurate impedance is required for the above-mentioned open area, it is necessary to change the width of the transmission line according to the length of the transmission line in order to obtain the same impedance. Therefore, the longer the transmission lines 64, 66, the thinner the transmission lines 64, 66 are required to obtain the same impedance. As shown in FIG. 5, a pair of transmission lines 64, 66 are provided in the sections 72, 74.
Is less than the width of another pair of transmission lines 68, 70.

FIG. 6 is a plan view of a flexible substrate 130 according to the second embodiment of the present invention. As shown in FIGS. 6 and 7, the first and second opening patterns are circular openings 160, 162, 164 having various sizes. Circular opening 16
The first and second arrangement shapes of 0, 162, 164 are transmission lines 90, 92, 94, as shown in FIGS. 6 and 7.
Related to 96, 98, 100 curves.

The circular apertures 160, 162, 164 provide a slow wave effect, compensating for timing effects and reducing undesired electromagnetic radiation more than if extra extra length was added. Various circular openings 160, 162,
The simplest way to implement 164 is transmission lines 90, 92, 94, 96, 98, 100 of varying lengths in the open area.
Is to design a matching percentage for. As shown in FIGS. 6 and 7, the transmission lines 90, 92
The longer is, the smaller is the percentage of circular openings 160. That is, the smaller the percentage of circular openings 160, the shorter the transmission time of transmission lines 90, 92. If the correct impedance is required in the above-mentioned aperture pattern area, different and matching widths for different lengths of the transmission line are needed to obtain the same impedance. Thus, if the length of the transmission lines 90, 92 is longer and the percentage of the circular openings 160 is smaller, then the width of the transmission lines 90, 92 can be reduced to obtain the same impedance. That is, as shown in FIG. 7, the width of the transmission line 90 is narrower than the width of the transmission line 94.

FIG. 8 is a sectional view taken along line 8-8 of FIG.

FIG. 9 is a plan view of the shielded flexible cable 210 of the third embodiment of the present invention. Cable 21
0 has the effect of diversifying the transmission time, and the matched length (about 32 cm) of the substrate 30 brings about the second mode harmonics (910 MHz) with the transmission frequency of 455 MHz.
As shown at 12 in FIG. 9, the cable 210
Is a turn portion having a predetermined small portion of a rectangular opening pattern 250 and gradually diversifying solid patterns 274 and 272. As shown in FIGS. 9 and 10, the first and second arrangement shapes of the rectangular opening pattern 250 are the same, and the transmission lines 260, 262, 264, 266, 268, 2 are the same.
Not related to the 70 curve. 10 is an enlarged view of a portion 10 in FIG. 9, and FIG. 11 is a sectional view taken along line 11-11 of FIG.

FIG. 12 is an enlarged view of a portion 12 in FIG. FIG. 13 is a sectional view taken along line 13-13 of FIG. If impedance accuracy is required, transmission line 2
64 and 266 are made smaller to meet the impedance requirements due to the increased capacitance of the solid patterns 272 and 244. As shown in FIGS. 12 and 13, the width of the transmission lines 264 and 266 is within the area of the solid patterns 272 and 274.
It is made thinner than 8, 270.

FIG. 14 is a plan view of the shielded flexible cable of the fourth embodiment of the present invention. The substrate 310 has a rectangular opening having an arrangement shape that does not relate to the curve of the substrate 310. FIG. 15 is an enlarged view of the portion 15 in FIG. 16 is a sectional view taken along line 16-16 of FIG.
Note that the rectangular opening patterns 354, 356, 35
8 is to have various aperture rectangles. The rectangular aperture patterns 354, 356, 358 provide a slow wave effect and compensate for timing effects resulting in less undesired electromagnetic radiation compared to the addition of an extra equivalent length. The simplest way to implement the rectangular aperture pattern 354, 356, 358 is to use transmission lines 290-29 of varying lengths.
2, 294-296, 298-300 to design a consistent percentage open area. Figure 1
4 and FIG. 15, transmission lines 290-292.
Becomes longer, the percentage of the rectangular opening pattern 354 becomes smaller. Therefore, as the percentage of the rectangular opening pattern 354 decreases, the transmission lines 290-292 become smaller.
Transmission time is reduced. If accurate impedances are required for the above-mentioned open areas, different and matching widths are needed for transmission lines of various lengths in order to have the same impedance. In order to obtain the same impedance, the rectangular opening pattern 35
The longer the length of transmission lines 290-292 with a smaller percentage of four, the narrower the width of transmission lines 290-292. Therefore, as shown in FIGS. 15 and 16, the width of the transmission lines 290-292 is smaller than the width of the transmission lines 264-296.

FIG. 17 is a plan view of a flexible substrate 372 according to the fifth embodiment of the present invention. The substrate 372 is a substrate 372.
The rectangular opening pattern has various arrangement shapes related to the curved portion of the. FIG. 18 is an enlarged view of a portion 18 in FIG. 19 is a sectional view taken along the line 19-19 of FIG.
Note that the rectangular opening patterns 460, 462, 46
4 provides a slow wave effect and compensates for timing effects, resulting in less unwanted electromagnetic radiation than would be the case with the addition of an extra equivalent length. These transmission lines 39
0 and 392 are rectangular aperture patterns 460 of different sizes for better shielding effect, as shown in FIG.
It needs to be connected to 462 and 464. The simplest way to implement the rectangular aperture pattern 460, 462, 464 is by varying length transmission lines 360-362, 364-36.
6, 368-370 to design a matching percentage of open area. As shown in FIGS. 17 and 18, as the transmission lines 360-362 become longer,
The percentage of the rectangular opening pattern 460 becomes smaller. Therefore, as the percentage of the rectangular opening pattern 460 decreases, the transmission time of the transmission lines 360-362 decreases. If accurate impedances are required for the above-mentioned open areas, different and matching widths are needed for transmission lines of various lengths in order to have the same impedance. In order to obtain the same impedance, the width of the transmission lines 360-362 is made narrower as the length of the transmission lines 360-362 having a smaller percentage of the rectangular opening pattern 460 is made longer. Therefore, as shown in FIGS.
The width of 62 is smaller than the width of transmission lines 364-366.

The above is a description of preferred embodiments of the present invention, and details of modifications that can be easily made based on the present invention,
All modifications are within the claims of the present invention.

[0048]

The present invention provides a substrate or a flexible cable having a shield plane with various opening patterns for controlling impedance and transmission time, that is, the present invention is flexible with a special shield plane. A substrate is provided, which is used in a low voltage differential transmission mode circuit, wherein the impedance of the transmission line of the substrate and the transmission time are controlled by a shield plane having an aperture pattern. The capacitance and slow wave effect related to the opening pattern and the layout shape related to the position of the opening pattern are used to improve the impedance and the transmission timing of the transmission line of the substrate.

[Brief description of drawings]

FIG. 1 is a plan view of a first embodiment of a shield substrate according to the present invention.

FIG. 2 is an enlarged view of two parts of FIG.

3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is an enlarged view of part 4 of FIG.
° Shows how to bend.

5 is a sectional view taken along line 5-5 of FIG.

FIG. 6 is a plan view of a second embodiment of the shield substrate according to the present invention.

FIG. 7 is an enlarged view of portion 7 in FIG.

8 is a sectional view taken along line 8-8 of FIG.

FIG. 9 is a plan view of a third embodiment of the shield substrate according to the present invention.

FIG. 10 is an enlarged view of portion 10 of FIG.

11 is a sectional view taken along line 11-11 of FIG.

FIG. 12 is an enlarged view of part 12 of FIG.

13 is a sectional view taken along line 13-13 of FIG.

FIG. 14 is a plan view of a fourth embodiment of the shield substrate according to the present invention.

FIG. 15 is an enlarged view of portion 15 of FIG.

16 is a sectional view taken along line 16-16 of FIG.

FIG. 17 is a plan view of a shield substrate according to a fifth embodiment of the present invention.

FIG. 18 is an enlarged view of portion 18 of FIG.

FIG. 19 is a sectional view taken along line 19-19 of FIG.

[Explanation of symbols]

60, 62, 64, 66, 68, 70 Transmission line 28, 40 Shield plane 30, 130, 372 Board or cable 88 DC power supply 54 Ground 82 Opening pattern 210, 310 Board or cable 72, 74 Solid pattern 50 Via 160, 162 164 circular apertures 90, 92, 94, 96, 98, 100 transmission lines 260, 262, 264, 266, 268, 270 transmission lines 354, 356, 358 rectangular aperture patterns 290, 292, 294, 296, 298, 300 transmissions Lines 460, 462, 464 Rectangular aperture patterns 360, 362, 364, 366, 368, 370 Transmission lines

Continuation of the front page (56) References JP-A-2-252299 (JP, A) JP-A-62-103906 (JP, A) Actually-opened Shou 60-124056 (JP, U) Special Table HEI 8-506696 (JP , A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H05K 1/02 H05K 9/00 H01B 7/08

Claims (40)

(57) [Claims] 1. In the substrate, The first predetermined shield shape, limited to the first plane
And a first set of predetermined aperture pattern positions,
A first set of predetermined opening patterns having a predetermined arrangement shape
And a predetermined first set of solid patterns placed at predetermined positions.
The first predetermined shield shape including turns and combinations
When, Second shield shape, limited to the second plane
A second set of predetermined aperture pattern positions,
A second set of predetermined opening patterns having a predetermined arrangement shape
And a predetermined second set of solid patterns placed at predetermined positions.
The second predetermined shield shape including turns and combinations
When, A signal conducting element, the first plane and the second plane
And a pair of differential mode signal-conducting elements disposed between the
A pair of signal-conducting elements limited to the middle of the
With virtual ground for differential mode signal conducting elements
And a signal conducting element, With The signal conducting element or the virtual ground is the first
And each predetermined position of the second predetermined shield shape
A substrate, characterized in that it is arranged on. 2. The substrate according to claim 1, wherein the opening pattern
The maximum dimension of the cable is the maximum that the signal conducting element can carry.
Characterized by being smaller than 1/20 wavelength of high frequency,
substrate. 3. The substrate according to claim 1, wherein the first and second substrates are provided.
The predetermined arrangement shape of is a grid,
Board. 4. The substrate according to claim 1, wherein the first and second substrates are provided.
The predetermined arrangement shape of the
Is a virtual ground of a pair of differential mode signal conducting elements.
A substrate, which is matched to the substrate. 5. The substrate according to claim 1, wherein a predetermined opening pattern is provided.
The turn is circular Substrate characterized by the above. 6. The substrate according to claim 1, wherein a predetermined opening pattern is provided.
A substrate characterized in that the turns are oval. 7. The substrate according to claim 1, wherein a predetermined opening pattern is provided.
A substrate having a rectangular turn. 8. The substrate according to claim 1, wherein a predetermined opening pattern is provided.
A substrate characterized in that the turns are diamond-shaped. 9. The solid pattern according to claim 1, wherein
The bent part is the bent part, the part that needs to be bent, or
Or both ends of the signal conducting element.
Board. 10. The substrate according to claim 1, wherein
2 aperture patterns and signal conducting elements are flexible
Board including a cable. 11. The substrate according to claim 1, wherein
Two planes are connected and a pair of differential mode signal transmission elements are connected.
Pointing to ground, power supply, power supply ground
Or the normal mode signal is transmitted by the signal conducting element.
The substrate is characterized in that it is transmitted through the board. 12. The substrate according to claim 1, wherein the opening pattern
Substrate having a symmetrical pattern. 13. The substrate according to claim 12, wherein a pair of differences is provided.
The virtual ground or signal of a signal-conducting element in motion mode.
The opening pattern of the transmission element is symmetrical
A substrate characterized by being determined in the center of. 14. The substrate according to claim 1, wherein
2, the predetermined shield shape has a predetermined opening pattern
A substrate including a conductive element. 15. The substrate according to claim 14, wherein the first combination
And a combination of predetermined opening patterns of the second set, first and second
The space of the conductive elements in the plane of each conductive element
Are aligned on the line with respect to
Impedance for transmission, transmission timing and power
Characterized by being designed to match magnetic emission control
Board. 16. The substrate according to claim 14, wherein the first and
The second plane conductive element is a thin film type conductive element.
Substrate characterized by being treated as a substrate. 17. The substrate according to claim 14, wherein the first and
Conduction in which the second shield shape has a predetermined opening pattern
The element includes the element and the second predetermined layout shape is offset
It is the same as the first predetermined arrangement shape with
The board to collect. 18. The substrate according to claim 17, wherein the opening pattern
The largest dimension of the signal is the signal transmitted to the signal conducting element.
It is smaller than 1/20 of the wavelength of the highest frequency of the No.
And the substrate. 19. The substrate according to claim 17, wherein the first combination
And a combination of predetermined opening patterns of the second set, first and second
The space of the conductive elements in the plane of each conductive element
Are aligned on the line with respect to
Impedance for transmission, transmission timing and power
Characterized by being designed to match magnetic emission control
Board. 20. The substrate according to claim 17, wherein the first and
The second predetermined layout shape is a grid and a predetermined offset
Is the grid spacing in the direction of the signal conducting element.
Substrate, characterized in that it is equal to 1/2 of the substrate. 21. The substrate of claim 17, wherein the first and
The second predetermined arrangement shape is in the direction of each signal conducting element.
A substrate, characterized in that it is matched with respect to. 22. The substrate according to claim 17, wherein a predetermined opening is provided.
The mouth pattern is a symmetrical pattern,
substrate. 23. The substrate according to claim 17, wherein a predetermined opening is provided.
A substrate having a circular mouth pattern. 24. The substrate according to claim 17, wherein a predetermined opening is provided.
Substrate characterized in that the mouth pattern is elliptical. 25. The substrate according to claim 17, wherein a predetermined opening is provided.
A substrate having a rectangular mouth pattern. 26. The substrate according to claim 17, wherein a predetermined opening is provided.
The mouth pattern is rhombus A substrate characterized by being processed. 27. The substrate according to claim 17, wherein the solid
The predetermined position of the pattern is the bent part, the part that needs to be bent
Or both ends of the signal conducting element.
The board to collect. 28. In the substrate, The first predetermined shield shape, limited to the first plane
And a predetermined arrangement including a set of predetermined aperture pattern positions
A set of predetermined opening patterns with shapes and predetermined positions
A set of predetermined solid patterns arranged in
Including the first predetermined shield shape, A signal-conducting element, which is parallel to the first plane.
A pair of differential mode signal transmission elements which are arranged on two planes.
A pair of differential mode signal conduction sensors defined in the middle of the
The signal transmission element with the virtual ground of
And Where the signal conducting element or virtual ground is
Being placed in a predetermined position with respect to a fixed shield shape
Substrate. 29. The substrate according to claim 28, wherein
A substrate, characterized in that the placement shape is a lattice. 30. The substrate according to claim 25, wherein
The shape of the signal transmission element is the direction or a pair of
Match the virtual ground of the signal-conducting element in the dynamic mode
A substrate, characterized in that 31. The substrate according to claim 28, wherein a predetermined opening is provided.
A substrate having a circular mouth pattern. 32. The substrate according to claim 28, wherein a predetermined opening is provided.
Substrate characterized in that the mouth pattern is elliptical. 33. The substrate according to claim 28, wherein a predetermined opening is provided.
A substrate having a rectangular mouth pattern. 34. The substrate according to claim 28, wherein a predetermined opening is provided.
A substrate having a rhombus-shaped mouth pattern. 35. The substrate of claim 28, wherein the solid
The predetermined position of the pattern is the bent part, the part that needs to be bent
Or both ends of the signal conducting element Special
The board to collect. 36. The substrate according to claim 28, wherein a predetermined opening is provided.
The mouth pattern is a symmetrical pattern,
substrate. 37. The substrate of claim 36, wherein the pair of differences
The virtual ground or signal of a signal-conducting element in motion mode.
The opening pattern of the transmission element is symmetrical
A substrate characterized by being determined in the center of. 38. The substrate according to claim 28, wherein
The conductive shape has a predetermined aperture pattern.
Substrate. 39. The substrate according to claim 38, wherein a predetermined opening is provided.
The maximum dimension of the mouth pattern is transmitted to the signal conducting element.
Is smaller than 1/20 of the wavelength of the highest frequency of the signal
Characteristic board. 40. The substrate of claim 38, wherein a set of locations
Constant aperture pattern, on line with respect to signal conducting element
Aligning first plane conductive element spaces and locations
The combination of fixed solid patterns is
Impedance, transmission timing and electromagnetic radiation control
It is designed to match your needs
Board.