Method, system and device for improving signal integrity of flexible circuit board and medium

Abstract

The invention provides a method, system and device for improving signal integrity of a flexible circuit board and a medium, and the method comprises the steps: determining the number of segments included in a wire, and enabling the adjacent segments to have angle change; after the number of the sections is determined, setting the angle of the grid according to the routing, namely judging whether the change of the angle between the adjacent sections of the routing exceeds a preset angle value or not; if not, determining the longest section in the routing section, and setting the angle of the grid in the reference area of the routing according to the angle of the section; if yes, the angle of the grid is set according to the size relation between the length of the wires and the preset length and the wires; wherein the setting of the angle of the grid according to the angle of the section is specifically as follows: the extension direction of a diagonal line of the grid is consistent with the extension direction of the section. According to the technical scheme, the manufacturing tolerance is considered, the grid angle is set according to bending on the basis that the signal integrity is not affected, and grid setting is simple and convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of flexible circuit boards, and in particular to a method, system, device and medium for improving signal integrity of flexible circuit boards. Background Art

[0002] The purpose of impedance control of flexible circuit boards is to ensure the stability of current transmission in the circuit and reduce signal reflection and interference. Impedance mismatch may cause signal loss, clock offset, signal overlap and other problems, and even affect the stability and reliability of the entire system; therefore, impedance control is particularly important for circuits that require high-speed signal transmission or high frequency.

[0003] For the purpose of impedance control, in flexible circuit boards, the reference ground generally uses a grid ground, which can help control the impedance of the signal line and ensure the quality of signal transmission; and the grid ground can make the flexible circuit board more flexible in terms of circuit and assembly. However, for the grid ground impedance model, whether it is single-ended or differential routing, it is necessary to run at the center intersection of the grid ground diamond structure as much as possible and maintain strict symmetry.

[0004] In actual engineering applications, in order to avoid the influence of stress, the routing will follow the outline of the FPC. Therefore, when there are multiple bending areas in the FPC outline, the FPC routing will also make multiple bends. In the face of such a curved routing, if the grid ground is always at a certain angle, its impedance will no longer match, resulting in poor signal transmission quality. Summary of the invention

[0005] The present invention provides a method, system, device and medium for improving the signal integrity of a flexible circuit board, so as to solve the problem in the prior art that the impedance of a grid ground is no longer matched when a bend occurs in a routing line.

[0006] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] According to a first aspect of the present invention, a method for improving signal integrity of a flexible circuit board is provided, wherein the flexible circuit board comprises: a grid layer and a routing layer distributed in a longitudinal direction; the routing layer comprises at least one routing line; the grid layer comprises a plurality of first copper wires and a plurality of second copper wires, the plurality of first copper wires are parallel to each other in a first direction, the plurality of second copper wires are parallel to each other in a second direction, and the plurality of first copper wires and the plurality of second copper wires intersect to form a plurality of grids;

[0008] The method comprises:

[0009] Determining the number of segments included in the routing, wherein there is an angle change between adjacent segments;

[0010] After the number of the segments is determined, the angle of the grid is set according to the routing, specifically including:

[0011] Determining whether the angle change between adjacent segments of the routing exceeds a preset angle value;

[0012] If not, determining the longest segment of the routing line, and setting the angle of the grid in the reference area of ​​the routing line according to the angle of the segment;

[0013] If yes, setting the angle of the grid according to the relationship between the length of the routing line and the preset length and the routing line;

[0014] The angle of the grid is set according to the angle of the segment in such a way that the extension direction of a diagonal line of the grid is consistent with the extension direction of the segment.

[0015] Optionally, the angle of the grid is set according to the relationship between the length of the routing line and the preset length and the routing line, specifically including:

[0016] If the length of the routing line is less than the preset length, determining the longest segment of the routing line, and setting the angle of the grid in the reference area of ​​the routing line according to the angle of the segment;

[0017] If the length of the routing line is greater than or equal to the preset length, the method further includes:

[0018] Determine the longest segment of the routing line, and set the angle of the grid in the reference area according to the angle of the segment;

[0019] Calculate the remaining length of the routing and determine whether it exceeds the preset length. If so, continue to execute: determine the longest segment of the routing and set the angle of the grid in the reference area according to the angle of the segment, until the remaining routing length is less than the preset length or there is one segment left in the routing, at which time the angle of the grid in the remaining reference area is set according to the angle of the longest segment or the remaining segment in the routing.

[0020] Optionally, after the number of the segments is determined and the angle of the grid is set according to the routing, the method further includes:

[0021] Starting from one end of the routing, the segments are judged one by one to determine whether the angle change between the segment and the next segment exceeds a preset angle value, and the segments whose angle changes between each other do not exceed the preset angle value are named as a segment of the same type;

[0022] Then, determining the longest segment of the routing specifically includes: determining the same segment of the routing and the longest segment; when the longest segment is a segment of the same type, setting the angle of the grid in the reference area of ​​the same segment according to the angle of the segment specifically includes: determining the longest segment of the same type, and setting the angle of the grid in the reference area of ​​the same type according to the angle of the segment;

[0023] Until the remaining length of the routing is less than the preset length or there is one segment of the routing, specifically: until the remaining length of the routing is less than the preset length or there is one segment of the routing or there is a similar segment of the routing; when there is a similar segment of the routing, the angle of the grid in the remaining reference area is set according to the angle of the longest segment of the similar segment.

[0024] Optionally, the reference area is determined by:

[0025] One end point of the line segment and a point where the outer contour of the flexible circuit board changes angle near the end point form a boundary of the reference area; the other end point of the line segment and a point where the outer contour of the flexible circuit board changes angle near the end point form another boundary of the reference area, and the area between the two boundaries forms the reference area of ​​the line segment;

[0026] When one of the endpoints of the route is the starting point or the end point of the route, the boundary corresponding to the endpoint is formed by the contour points on both sides of the flexible circuit board corresponding to the endpoint in the horizontal direction.

[0027] Optionally, before determining the number of segments included in the routing, the method further includes: determining a reference routing, specifically including:

[0028] Determining the number of the routing lines, and if the number of the routing lines is one, determining the routing line as a reference routing line;

[0029] If the number of the routing lines is greater than one, determining whether a differential signal line is included, and if so, determining the differential signal line as a reference routing line; if not, determining the routing line with the fastest signal transmission speed as the reference routing line;

[0030] Correspondingly, determining the number of segments included in the routing line specifically includes: determining the number of segments included in the reference routing line;

[0031] The angle of the grid is set according to the routing, specifically: the angle of the grid is set according to the reference routing.

[0032] Optionally, when the differential signal line is determined to be a reference line, the method is executed for one of the differential signal lines;

[0033] Wherein, when the angle change between adjacent segments of the routing line exceeds a preset angle value, and the length of the routing line is greater than or equal to the preset length, the reference area is determined using two differential signal lines, specifically including:

[0034] The endpoints on the same side of the segment of the routing corresponding to the two differential signal lines each form a boundary of the reference area with a point where the outer contour of the flexible circuit board changes angle close to the endpoint and located on one side of the differential signal line; the endpoints on the other side of the segment of the routing corresponding to the two differential signal lines each form another boundary of the reference area with a point where the outer contour of the flexible circuit board changes angle close to the endpoint and located on one side of the differential signal line.

[0035] Optionally, after setting the angle of the grid according to the reference line, the method further includes: setting the position of the grid according to the reference line, specifically including:

[0036] If the reference line is a differential signal line, the vertical projection of a diagonal line of the grid is made to coincide with the extension direction of the intermediate axis of the differential signal line; otherwise, the vertical projection of a diagonal line of the grid is made to coincide with the extension direction of the reference line.

[0037] Optionally, the preset length is determined by a speed of a signal transmitted in the routing and a rise time of the signal transmitted.

[0038] Optionally, determining the number of segments included in the routing specifically includes: taking one end of the routing as a starting point, and based on a change in routing direction, determining that the routing is a different segment before and after the direction change.

[0039] Optionally, after setting the angle of the grid according to the routing, the method further includes:

[0040] On the grid stratum, a third copper wire is arranged in a reference area corresponding to the segment of the routing line located in the corner area of ​​the flexible circuit board, and a vertical projection of the third copper wire coincides with the segment of the routing line.

[0041] Optionally, the first direction is perpendicular to the second direction.

[0042] Optionally, the routing layer includes a copper grid, and the copper grid avoids the routing.

[0043] Optionally, the position and direction of the grid copper are consistent with the position and direction of a grid formed by the intersection of the first copper wire and the second copper wire at a vertically corresponding position.

[0044] According to a second aspect of the present invention, a system for improving signal integrity of a flexible circuit board is provided, wherein the flexible circuit board comprises: a grid layer and a routing layer distributed in a longitudinal direction; the routing layer comprises at least one routing line; the grid layer comprises a plurality of first copper wires and a plurality of second copper wires, the plurality of first copper wires are parallel to each other in a first direction, the plurality of second copper wires are parallel to each other in a second direction, and the plurality of first copper wires intersect with the plurality of second copper wires to form a plurality of grids;

[0045] The system comprises:

[0046] a segment number determination module, which is used to determine the number of segments included in the routing, and there is an angle change between adjacent segments;

[0047] A grid angle setting module, which is used to set the angle of the grid according to the routing; it specifically includes:

[0048] A preset angle value judgment module, which is used to judge whether the angle change between adjacent segments of the routing exceeds a preset angle value;

[0049] A first setting module, which is used to determine the longest segment of the routing line when the angle change between adjacent segments of the routing line does not exceed a preset angle value, and set the angle of the grid in the reference area of ​​the routing line according to the angle of the segment;

[0050] A second setting module, which is used to set the angle of the grid according to the relationship between the length of the route and the preset length and the route when the angle change between adjacent segments of the route exceeds a preset angle value;

[0051] The angle of the grid is set according to the angle of the segment in such a way that the extension direction of a diagonal line of the grid is consistent with the extension direction of the segment.

[0052] According to a third aspect of the present invention, there is provided an electronic device, comprising:

[0053] processor;

[0054] and, a memory for storing processor-executable instructions;

[0055] The processor implements the steps in the above method by running the executable instructions.

[0056] According to a fourth aspect of the present invention, there is provided a storage medium having a computer program stored thereon, wherein the computer program implements the steps in the above-mentioned method when executed by a processor.

[0057] The method, system, device and medium for improving the signal integrity of a flexible circuit board provided by the present invention compare the angle change between adjacent segments of the routing with a preset angle value, and the setting of the preset angle value takes into account the manufacturing tolerance; if there is no angle exceeding the preset angle value, the angle of the grid is set according to the angle of the longest segment, and if there is an angle exceeding the preset angle value, it means that the routing has a relatively large bend, and at this time, the size relationship between the length of the routing and the preset length is judged, and the angle of the grid is determined based on this; the setting of the preset length takes into account the influence of the routing length on the signal integrity, and the angle of the grid is set accordingly. In summary, the influence of the manufacturing tolerance on the routing angle is taken into account, and the routing bend and the routing length are comprehensively considered to set the angle of the grid, and the grid angle is set according to the bend without affecting the signal integrity. The setting of the grid angle is simple and convenient, and can ensure that the routing impedance mutation is controllable, thereby ensuring signal integrity. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0059] Figure 1 A partial top view of a wiring layer of a flexible circuit board according to an embodiment of the present invention;

[0060] Figure 2 A partial top view of the network lower layer of a flexible circuit board according to an embodiment of the present invention;

[0061] Figure 3 A partial top perspective view of a flexible circuit board according to an embodiment of the present invention;

[0062] Figure 4 A flow chart of a method for improving signal integrity of a flexible printed circuit board according to an embodiment of the present invention;

[0063] Figure 5 A schematic diagram of dividing the segments of a routing line according to an embodiment of the present invention;

[0064] Figure 6 A schematic diagram of dividing the segments of a routing line according to another embodiment of the present invention;

[0065] Figure 7 A schematic diagram of naming similar segments according to an embodiment of the present invention;

[0066] Figure 8 A schematic diagram of dividing a reference area for routing according to an embodiment of the present invention;

[0067] Fig. 9 A schematic diagram of dividing the reference area for routing according to another embodiment of the present invention;

[0068] Fig.10 A schematic diagram of wiring and grid positions according to another embodiment of the present invention;

[0069] Fig.11 A schematic diagram of the arrangement of mesh copper on a routing layer according to another embodiment of the present invention;

[0070] Fig.12 A schematic diagram of a system for improving signal integrity of a flexible printed circuit board according to an embodiment of the present invention;

[0071] Fig.13 is a schematic diagram of an electronic device according to an embodiment of the present invention;

[0072] Description of reference numerals:

[0073] 1-Flexible circuit board;

[0074] 11- routing layer;

[0075] 111-Line routing;

[0076] 112-first boundary;

[0077] 113-Second boundary;

[0078] 114-third boundary;

[0079] 115-Fourth Boundary;

[0080] 116-Fifth Boundary;

[0081] 117-grid copper;

[0082] 12-Network stratum;

[0083] 121-first copper wire;

[0084] 122- second copper wire;

[0085] 21-segment quantity determination module;

[0086] 22-Grid angle setting module;

[0087] 221-preset angle value judgment module;

[0088] 222-first setting module;

[0089] 223-second setting module;

[0090] 31- Processor,

[0091] 32-internal bus,

[0092] 33- Network interface,

[0093] 34-Memory,

[0094] 35-Memory. DETAILED DESCRIPTION

[0095] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0096] In the description of the specification of the present invention, it is necessary to understand that the orientation or position relationship indicated by the terms "upper part", "lower part", "upper end", "lower end", "lower surface", "upper surface", etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0097] In the description of the present specification, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0098] In the description of the present invention, "plurality" means a plurality, such as two, three, four, etc., unless otherwise clearly and specifically defined.

[0099] In the description of the present invention, unless otherwise clearly specified and limited, the term "connection" and other terms should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0100] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0101] In one embodiment, a method for improving the signal integrity of a flexible circuit board is provided. Figure 1 The flexible circuit board 1 includes a grid layer and a wiring layer distributed in the longitudinal direction. Figure 1 This is a top view of the wiring layer of the flexible circuit board. Figure 2 This is a top view of the grid formation of the flexible circuit board. Figure 3 The diagram is a partial top view of a flexible circuit board, and the positional relationship between the grid layer and the wiring layer is not shown. The wiring layer includes at least one wiring 111, such as Figure 1 As shown; the grid formation includes a plurality of first copper wires 121 and a plurality of second copper wires 122, the plurality of first copper wires 121 are parallel to each other in a first direction, the plurality of second copper wires 122 are parallel to each other in a second direction, and the plurality of first copper wires and the plurality of second copper wires intersect to form a plurality of grids, such as Figure 2 shown.

[0102] Please refer to Figure 4 , the method comprising:

[0103] S11: Determine the number of segments included in the routing, and there is an angle change between adjacent segments.

[0104] Specifically, based on the change in the routing direction, it is determined that the routing sections before and after the direction change are different sections.

[0105] As an implementation method, the number of segments included in a route can be determined by detecting the direction of the route starting from one end of the route after the route is drawn. When the direction of the route changes, the segment before the position where the change occurs is defined as one segment; then detection is performed until the other end of the route.

[0106] As another implementation, the number of segments included in the route can also be determined during the route drawing process. At the beginning of the route drawing, the number of segments included in the route is 1. During the route drawing process, when the direction of the drawn route changes, the number of segments included in the route is increased by 1 until the route drawing is completed.

[0107] Please refer to Figure 5-Figure 6 ,like Figure 5 or Figure 6 The number of segments included in the routing shown is 5, starting from one end of the routing to the other end, namely: ①, ②, ③, ④, ⑤.

[0108] S12: After the number of segments is determined, set the grid angle according to the routing, including:

[0109] S121: Determine whether the angle change between adjacent segments of the routing exceeds a preset angle value.

[0110] As an implementation manner, the preset angle value may be any value between 0° and 20°, such as 10°, and the preset angle value is determined based on manufacturing tolerance.

[0111] As an example, please refer to Figure 5 ,like Figure 5 In the routing shown, the angle values ​​between ① and ②, between ② and ③, between ③ and ④, and between ④ and ⑤ are all smaller than the preset angle value, that is, the angle change value between adjacent segments of the routing does not exceed the preset angle value, then enter S122.

[0112] In different embodiments, if the number of routing segments is 1, it is also included in this case, and the process goes to S122.

[0113] As another example, please refer to Figure 6 ,like Figure 6 In the routing shown, the angle values ​​between ① and ②, between ② and ③, between ③ and ④, and between ④ and ⑤ are all greater than the preset angle value, that is, if the angle change value between adjacent segments of the routing exceeds the preset angle value, then enter S123.

[0114] Of course, in the above embodiment, the number of angle change values ​​between adjacent segments of the routing that exceeds the preset angle value exceeds one. In different embodiments, as long as the angle change value between one adjacent segment exceeds the preset angle value, it is judged as this situation and enters S123.

[0115] S122: If not, determine the longest segment in the routing, and set the angle of the grid in the reference area of ​​the routing according to the angle of the segment.

[0116] The angle of the grid is set according to the angle of the segment in such a way that the extension direction of a diagonal line of the grid is consistent with the extension direction of the segment.

[0117] As an example, the first direction of the first copper wire is perpendicular to the second direction of the second copper wire, that is, the formed grid is a square grid, such as Figure 2 As shown; in addition, the angle of the routing and the angle of the grid can both be referenced to the horizontal direction, that is, the routing angle is the angle between the routing direction and the horizontal direction, and the grid angle is the angle between the first copper wire, the second copper wire and the horizontal direction. Then the angle of the grid is set according to the angle of the segment: if the angle of the routing segment is a, then the angle of the first copper wire is 45°+a, and the angle of the second copper wire is 135°+a.

[0118] In different embodiments, the first direction and the second direction may not be perpendicular, and the formed grid may be a diamond grid.

[0119] Preferably, the interval between adjacent first copper wires and the interval between adjacent second copper wires are respectively the same, and the intervals between the two are the same.

[0120] For S122, if the direction of the routing changes very little (less than the preset angle value) or does not change, the grid corresponding to the routing can be set to the same angle, which will not affect the integrity of the signal. If the number of segments is greater than 1, the angle of the grid is set with the angle of the longest segment as a reference, which can ensure that the angle of the grid matches the angle of the routing to the greatest extent.

[0121] Of course, the above S122 also includes the case where the number of segments is 1. In this case, the longest segment of the routing is the routing itself, and the angle of the grid in the reference area of ​​the routing is set according to the angle of the routing.

[0122] S123: If yes, the angle of the grid is set according to the relationship between the length of the routing and the preset length and the routing.

[0123] As an implementation method, the preset length is determined based on whether the length has an impact on signal integrity. When the transmission delay of the signal in the routing is greater than 20% of the signal rise time, the waveform of the signal will be significantly affected, resulting in ringing, which will cause the stability and reliability of the signal to decrease. Assuming that the transmission speed of a certain signal is V (in / ns), the rise time is Tr (ns), the length of a certain routing section is L (in), and the signal delay is TD (ns), Tr*20% ≤ TD = L / V, that is, when 0.2Tr·V ≤ L, the impact on signal integrity is relatively small, otherwise the impact on signal integrity is relatively large.

[0124] In one implementation, the preset length is determined by the speed of the signal transmitted in the routing and the rise time of the signal transmitted. For example, the preset length may be set to 0.2Tr·V.

[0125] In different implementations, in order to further improve signal integrity, the preset length may be set with a margin, that is, it may be set smaller than 0.2Tr·V, such as Tr·V / 6.

[0126] Determine the relationship between the length of the trace and the preset length, and set the angle of the grid accordingly, including:

[0127] S1231: If the length of the routing is less than the preset length, it means that although the routing is bent, the impact of this routing segment on signal integrity is relatively small. At this time, the angle of the grid corresponding to this routing segment does not need to be changed according to the angle of the routing, and the same angle can be used. At this time, you can refer to the angle setting method in S122, that is, determine the longest segment in the routing segment, and set the angle of the grid in the reference area of ​​the routing according to the angle of this segment.

[0128] S1232: If the length of the routing is greater than or equal to the preset length, it means that this section of routing has a greater impact on signal integrity. At this time, the angle of the grid needs to be changed according to the angle of the routing to ensure impedance matching, thereby reducing signal reflection and distortion and improving signal integrity.

[0129] If the length of the trace is greater than or equal to the preset length, the angle of the grid needs to change according to the angle of the trace, including:

[0130] S12321: Determine the longest segment in the routing, and set the angle of the grid in its reference area according to the angle of the segment.

[0131] As an example, please refer to Figure 6 , the number of segments included in the route is 5, starting from one end of the route, they are: ①, ②, ③, ④, ⑤. Assuming that the length of the route is greater than the preset length, and ① is the longest of the segments of the route, then the angle of the grid in the reference area ① is set according to the angle of ①, so that the extension direction of a diagonal line of the grid is the same as the extension direction of ①.

[0132] S12322: Calculate the length of the remaining routing and determine whether it exceeds the preset length. If so, continue to execute: determine the longest segment in the routing (i.e., the remaining segments of the routing), and set the angle of the grid in the reference area according to the angle of the segment, until the remaining routing length is less than the preset length or there is one segment left in the routing. If the remaining routing length is less than the preset length, set the angle of the grid in the remaining reference area according to the longest segment in the remaining routing; if there is one segment left in the routing, set the angle of the grid in the remaining reference area according to the angle of the remaining segment.

[0133] As an example, please refer to Figure 6 After the angle of the grid in the reference area of ​​① is set, the length of the remaining routing is calculated, which is the total length of ②, ③, ④, and ⑤, to determine whether it exceeds the preset length. If it still exceeds the preset length, the longest length among these segments is determined. If ③ is the longest segment among the remaining routing segments, the angle of the grid in the reference area of ​​③ is set according to the angle of ③, so that the extension direction of a diagonal line of the grid is the same as the extension direction of ③. Then, the length of the remaining routing is calculated again, which is the total length of ②, ④, and ⑤, to determine whether it exceeds the preset length. If it does not exceed the preset length, the longest length among these segments is determined. If ② is the longest length among these segments, the angle of the grid in the remaining reference area (i.e., the reference area corresponding to ②, ④, and ⑤) is set according to the angle of ②.

[0134] Above Figure 6In the example shown, segments ② and ④ of the corner region are straight line segments. In different embodiments, the segments of the corner region may also be arc segments. When the segments of the corner region are arc segments, and the length of the arc segments is greater than the preset length, which has an impact on signal integrity, preferably, the arc segments may be divided into N equal parts, and the angle of the grid in each equally divided reference region may be set separately, and the angle of the grid in each equally divided reference region is based on the tangent direction of the equally divided arc segments.

[0135] In one embodiment, after the number of segments is determined and the angle of the grid is set according to the routing, it also includes:

[0136] S21: Starting from one end of the routing, segments are judged one by one to determine whether the angle change between them and the next segment exceeds a preset angle value. For consecutive segments whose angle changes do not exceed the preset angle value, they are named as segments of the same type.

[0137] Based on the setting of S21 above, the longest segment in the routing is determined specifically as follows: the same segment of the routing and the longest segment are determined; when the longest segment is a segment of the same type, the angle of the grid in the reference area of ​​the same segment is set according to the angle of the segment. Specifically, the longest segment in the same type is determined, and the angle of the grid in the reference area of ​​the same type is set according to the angle of the segment.

[0138] Until the remaining routing length is less than the preset length or there is one segment left in the routing, specifically: until the remaining routing length is less than the preset length or there is one segment left in the routing or there is one segment of the same type left in the routing; when there is one segment of the same type left in the routing, the angle of the grid in the remaining reference area is set according to the angle of the longest segment in the remaining segments of the same type. When the remaining routing length is less than the preset length or there is one segment left in the routing, please refer to the description in S12322 for the angle setting of the grid, which will not be repeated here.

[0139] As an example, see Figure 7 , the number of segments included in the routing is 6, starting from one end of the routing, they are: ①, ②, ③, ④, ⑤, ⑥. Starting from the side of ①, the segments are judged one by one. Assuming that the angle change between ① and ②, and between ② and ③ does not exceed the preset angle value, ①, ②, ③ are named as a segment of the same type (e.g., they can be the first segment of the same type). If the angle change between ③ and ④ exceeds the preset angle value, they are not named. If the angle change between ④ and ⑤ does not exceed the preset angle value, ④ and ⑤ are named as another segment of the same type (e.g., they can be the second segment of the same type). If the angle change between ⑤ and ⑥ exceeds the preset angle value, they are not named.

[0140] After the same segment is named, the same segment can be used as a whole to determine the grid angle setting. Then determine the longest segment in the route or the remaining route. The route or the remaining route may only include the same segment, or only include segments, or both the same segment and segments. At this time, determine the longest segment is to determine the same segment and the longest segment. Please continue to refer to Figure 7 , assuming that the length of the routing exceeds the preset length, then, first, when making the first longest length judgment, the routing includes both similar segments and segments. At this time, the judgment is: the same segment and the longest segment. Assuming that the longest length is the first similar segment, the angle of the grid in the reference area corresponding to the first similar segment is set first. The setting can be set according to the angle of the longest segment in the first similar segment. Assuming that ① is the longest segment in the first similar segment, then the angle of the grid in the reference area of ​​the first similar segment is set according to the angle of ①. The grid setting principle of the remaining routing reference areas is similar to this and will not be repeated here.

[0141] In the above embodiment, after the same type of segments are named, the angle settings of the grids of the same type of segments can be performed together without having to set them one by one, which further simplifies the angle setting of the grids.

[0142] In one embodiment, please refer to Figure 8 , the reference area is determined by:

[0143] One end point of the line segment and the point where the outer contour of the flexible circuit board changes angle near the end point form a boundary of the reference area; the other end point of the line segment and the point where the outer contour of the flexible circuit board changes angle near the end point form another boundary of the reference area, and the area between the two boundaries forms the reference area of ​​the line segment, that is, the area surrounded by the two boundaries and the two sides of the flexible circuit board 1 is the reference area of ​​the line segment. Figure 8 Taking the second segment of routing ② shown as an example, its two end points and the points where the angles of the outer contours on both sides of the flexible circuit board close to the end points change respectively form the first boundary 112 and the second boundary 113 of the reference area. The first boundary 112, the second boundary 113 and the two side edges of the flexible circuit board 1 enclose the reference area of ​​this segment of routing.

[0144] When one of the endpoints of the route is the starting point or end point of the route, such as Figure 8 The left endpoint of ① and the right endpoint of ③ are shown, and the boundaries corresponding to the endpoints are formed by the contour points on both sides of the flexible circuit board corresponding to the endpoints and the horizontal direction, such as Figure 8 As shown in the third boundary 114 in FIG.

[0145] In addition, when the boundaries of the reference areas of the two adjacent segments to the routing segment are determined, the reference area of ​​the routing segment has been determined, that is, the area between the two segments, and at this time, there is no need to use boundary lines for determination.

[0146] In one embodiment, before determining the number of segments included in the routing, the method further includes: determining a reference routing, specifically including:

[0147] Determine the number of routing lines. If the number of routing lines is one, determine that the routing line is a reference routing line.

[0148] If the number of routing lines is greater than one, it is determined whether differential signal lines are included. If differential signal lines are included, generally differential signal lines are the main ones, and the differential signal lines are determined as reference routing lines; if not, the routing line with the fastest signal transmission speed is determined as the reference routing line. Correspondingly, the subsequent steps are all performed on the reference routing line.

[0149] In the above embodiment, the reference routing is determined, and the angle of the grid is set based on the reference routing, that is, the angle of the grid is based on the most important routing.

[0150] Specifically, determining the number of segments included in the routing is specifically: determining the number of segments included in the reference routing; setting the angle of the grid according to the routing is specifically: setting the angle of the grid according to the reference routing.

[0151] In one embodiment, when the reference routing line is a differential signal line, when determining the number of routing segments as described in the above embodiment, determining whether the angle change between adjacent routing segments exceeds a preset angle value, determining the size relationship between the routing length and the preset length, and determining the routing segment or the longest segment of the same type or the remaining routing segments, all can be performed for only one of the differential signal lines. However, in this embodiment, when determining whether the angle change between adjacent routing segments exceeds a preset angle value, and the routing length is greater than or equal to the preset length, two differential signal lines are used when determining the reference area. Please refer to Fig. 9 Specifically, the endpoints on the same side of the segment of the line corresponding to the two differential signal lines each form a boundary of the reference area with a point where the outer contour of the flexible circuit board close to the endpoint and located on one side of the differential signal line changes angle (such as Fig. 9 The endpoints on the other side of the segment of the line corresponding to the two differential signal lines each form another boundary of the reference area (such as the point where the angle of the outer contour of the flexible circuit board close to the endpoint and located on one side of the differential signal line changes) Fig. 9 The fifth boundary 116 in FIG.

[0152] In the above embodiment, two differential signal lines are used to determine the reference area, which can make the grid angle setting more accurate. Of course, in different embodiments, since the two differential signal lines are very close, the reference area can also be determined using one of the differential signal lines.

[0153] In another embodiment, after setting the angle of the grid according to the reference line, S12 further includes:

[0154] S31: Set the grid position according to the reference routing, including:

[0155] If the reference trace is a differential signal line, make the vertical projection of a diagonal line of the grid coincide with the extension direction of the middle axis of the differential signal line, such as Figure 3 Otherwise, make the vertical projection of a diagonal line of the grid coincide with the extension direction of the reference trace, as shown in Fig.10 As shown in the figure, only part of the routing and part of the grid are shown.

[0156] In one embodiment, after S12 sets the angle of the grid according to the routing, it also includes:

[0157] S41: On the grid layer, a third copper wire is set in a reference area corresponding to the segment of the routing line located in the corner area of ​​the flexible circuit board, and the vertical projection of the third copper wire coincides with the segment of the routing line. That is, for the routing line in the corner area, a copper wire corresponding to the segment of the routing line is pulled vertically to make the impedance more matched.

[0158] In another embodiment, the routing layer includes a copper mesh 117, and the copper mesh avoids the routing. Fig.11 , the mesh copper 117 can be distributed on both sides of the routing. Mesh copper is also laid on the routing layer to improve the EMC anti-interference performance and signal quality of the flexible circuit board.

[0159] As an implementation manner, the position and direction of the grid copper are consistent with the position and direction of the grid formed by the intersection of the first copper wire and the second copper wire at a perpendicular corresponding position.

[0160] In one embodiment, a system for improving the signal integrity of a flexible circuit board is further provided, wherein the flexible circuit board includes: a grid layer and a routing layer distributed in a longitudinal direction; the routing layer includes at least one routing line; the grid layer includes a plurality of first copper wires and a plurality of second copper wires, the plurality of first copper wires are parallel to each other in a first direction, the plurality of second copper wires are parallel to each other in a second direction, and the plurality of first copper wires intersect with the plurality of second copper wires to form a plurality of grids;

[0161] Please refer to Fig.12 , the system comprises:

[0162] a segment number determination module 21, which is used to determine the number of segments included in the routing, and there is an angle change between adjacent segments;

[0163] The grid angle setting module 22 is used to set the angle of the grid according to the routing; it specifically includes:

[0164] A preset angle value determination module 221, which is used to determine whether the angle change between adjacent segments of the routing line exceeds a preset angle value;

[0165] A first setting module 222, which is used to determine the longest segment of the route when the angle change between adjacent segments of the route does not exceed a preset angle value, and set the angle of the grid in the reference area of ​​the route according to the angle of the segment;

[0166] A second setting module 223, which is used to set the angle of the grid according to the relationship between the length of the route and the preset length and the route when the angle change between adjacent segments of the route exceeds a preset angle value;

[0167] The angle of the grid is set according to the angle of the segment in such a way that the extension direction of a diagonal line of the grid is consistent with the extension direction of the segment.

[0168] In one embodiment, the second setting module is specifically used to:

[0169] If the length of the routing is less than the preset length, the longest segment of the routing is determined, and the angle of the grid in the reference area of ​​the routing is set according to the angle of the segment;

[0170] If the length of the trace is greater than or equal to the preset length, then:

[0171] Determine the longest segment of the routing, and set the angle of the grid in its reference area based on the angle of that segment;

[0172] Calculate the remaining length of the routing and determine whether it exceeds the preset length. If so, continue to execute: determine the longest segment in the routing, and set the angle of the grid in the reference area according to the angle of the segment, until the remaining routing length is less than the preset length or there is one segment left in the routing. At this time, set the angle of the grid in the remaining reference area according to the angle of the longest segment in the remaining routing or the remaining segment.

[0173] In another embodiment, the system further comprises:

[0174] The same-segment naming module is used to judge the segments one by one from one end of the routing after the number of segments is determined, to determine whether the angle change between it and the next segment exceeds the preset angle value, and to name the segments whose angle changes between each other do not exceed the preset angle value as a same-segment segment.

[0175] In yet another embodiment, the system further comprises:

[0176] The reference routing determination module is used to determine the reference routing before the number of segments is determined, specifically for:

[0177] Determine the number of routing lines. If the number of routing lines is one, determine that the routing line is a reference routing line.

[0178] If the number of routing lines is greater than one, it is determined whether a differential signal line is included. If so, the differential signal line is determined as a reference routing line; if not, the routing line with the fastest signal transmission speed is determined as the reference routing line.

[0179] In yet another embodiment, the system further comprises:

[0180] The grid position setting module is used to set the grid position according to the reference line after the grid angle is set. It is specifically used for:

[0181] If the reference trace is a differential signal line, the vertical projection of a diagonal line of the grid is made to coincide with the extension direction of the middle axis of the differential signal line; otherwise, the vertical projection of a diagonal line of the grid is made to coincide with the extension direction of the reference trace.

[0182] In one embodiment, the system further comprises:

[0183] The third copper wire setting module is used to set the third copper wire in the reference area corresponding to the segment of the routing located in the corner area of ​​the flexible circuit board on the grid layer after the grid angle is set, and the vertical projection of the third copper wire coincides with the segment of the routing.

[0184] In one embodiment, the system further comprises:

[0185] The grid copper setting module is used to set the grid copper on the routing layer after the grid angle is set, and the grid copper avoids the routing position.

[0186] In one embodiment, an electronic device is also provided, please refer to Fig.13. At the hardware level, the device includes a processor 31, an internal bus 32, a network interface 33, a memory 34 and a storage 35, and of course may also include hardware required for other services. One or more embodiments of the present invention can be implemented based on software, such as the processor 31 reading the corresponding computer program from the storage 35 into the memory 34 and then running it. Of course, in addition to the software implementation, one or more embodiments of the present invention do not exclude other implementation methods, such as logic devices or a combination of software and hardware, etc., that is, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic devices.

[0187] The systems, devices, modules or units described in the above embodiments may be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer, which may be in the form of a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email transceiver, a game console, a tablet computer, a wearable device or a combination of any of these devices.

[0188] In a typical configuration, a computer includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0189] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0190] Computer-readable media include permanent and non-permanent, removable and non-removable media that can be used to store information by any method or technology. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, disk storage, quantum memory, graphene-based storage media or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include temporary computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0191] In summary, in the above embodiments of the present invention, firstly, the angle of the grid is set based on whether the angle change between adjacent segments of the routing exceeds the preset angle value, and considering the existence of manufacturing tolerances in the production and processing of flexible circuit boards, the angle change that does not exceed the preset angle value is ignored, so that the setting of the grid is more convenient and simple; in addition, for the angle change that exceeds the preset angle value, the relationship between the length of the routing and the preset length is considered, and the grid angle is set according to the bend without affecting the signal integrity, which further simplifies the setting of the grid angle.

[0192] The above describes specific embodiments of the present invention. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0193] In the description of this specification, the description with reference to the terms "an implementation", "an example", "a specific implementation process", "an example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0194] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the signal integrity of a flexible circuit board, characterized in that: The flexible circuit board includes: a grid layer and a routing layer distributed in the longitudinal direction; the routing layer includes at least one routing line; the grid layer includes a plurality of first copper wires and a plurality of second copper wires, the plurality of first copper wires are parallel to each other in a first direction, the plurality of second copper wires are parallel to each other in a second direction, and the plurality of first copper wires and the plurality of second copper wires intersect to form a plurality of grids; The method comprises: Determining the number of segments included in the routing, wherein there is an angle change between adjacent segments; After the number of the segments is determined, the angle of the grid is set according to the routing, specifically including: Determining whether the angle change between adjacent segments of the routing exceeds a preset angle value; If not, determining the longest segment of the routing line, and setting the angle of the grid in the reference area of ​​the routing line according to the angle of the segment; If yes, setting the angle of the grid according to the relationship between the length of the routing line and the preset length and the routing line; The angle of the grid is set according to the angle of the segment in such a way that the extension direction of a diagonal line of the grid is consistent with the extension direction of the segment.

2. The method according to claim 1, characterized in that The angle of the grid is set according to the relationship between the length of the routing line and the preset length and the routing line, specifically including: If the length of the routing line is less than the preset length, determining the longest segment of the routing line, and setting the angle of the grid in the reference area of ​​the routing line according to the angle of the segment; If the length of the routing line is greater than or equal to the preset length, the method further includes: Determine the longest segment of the routing line, and set the angle of the grid in the reference area according to the angle of the segment; Calculate the remaining length of the routing and determine whether it exceeds the preset length. If so, continue to execute: determine the longest segment of the routing and set the angle of the grid in the reference area according to the angle of the segment, until the remaining length of the routing is less than the preset length or there is one segment left in the routing, at which time the angle of the grid in the remaining reference area is set according to the angle of the longest segment or the remaining segment in the routing.

3. The method according to claim 2, characterized in that After the number of segments is determined and the angle of the grid is set according to the routing, it also includes: Starting from one end of the routing, the segments are judged one by one to determine whether the angle change between the segment and the next segment exceeds a preset angle value, and the segments whose angle changes between each other do not exceed the preset angle value are named as a segment of the same type; Then, determining the longest segment of the routing specifically includes: determining the same segment of the routing and the longest segment; when the longest segment is a segment of the same type, setting the angle of the grid in the reference area of ​​the same segment according to the angle of the segment specifically includes: determining the longest segment of the same type, and setting the angle of the grid in the reference area of ​​the same type according to the angle of the segment; Until the remaining length of the routing is less than the preset length or there is one segment of the routing, specifically: until the remaining length of the routing is less than the preset length or there is one segment of the routing or there is a similar segment of the routing; when there is a similar segment of the routing, the angle of the grid in the remaining reference area is set according to the angle of the longest segment of the similar segment.

4. The method according to claim 2, characterized in that: The method for determining the reference area is: One end point of the line segment and a point where the outer contour of the flexible circuit board changes angle near the end point form a boundary of the reference area; the other end point of the line segment and a point where the outer contour of the flexible circuit board changes angle near the end point form another boundary of the reference area, and the area between the two boundaries forms the reference area of ​​the line segment; When one of the endpoints of the route is the starting point or the end point of the route, the boundary corresponding to the endpoint is formed by the contour points on both sides of the flexible circuit board corresponding to the endpoint in the horizontal direction.

5. The method according to claim 4, characterized in that Before determining the number of segments included in the routing, the method further includes: determining a reference routing, specifically including: Determining the number of the routing lines, and if the number of the routing lines is one, determining the routing line as a reference routing line; If the number of the routing lines is greater than one, determining whether a differential signal line is included, and if so, determining the differential signal line as a reference routing line; if not, determining the routing line with the fastest signal transmission speed as the reference routing line; Correspondingly, determining the number of segments included in the routing line specifically includes: determining the number of segments included in the reference routing line; The angle of the grid is set according to the routing, specifically: the angle of the grid is set according to the reference routing.

6. The method according to claim 5, characterized in that When the differential signal line is determined to be a reference line, the method is executed for one of the differential signal lines; Wherein, when the angle change between adjacent segments of the routing line exceeds a preset angle value, and the length of the routing line is greater than or equal to the preset length, the reference area is determined using two differential signal lines, specifically including: The endpoints on the same side of the segment of the routing corresponding to the two differential signal lines each form a boundary of the reference area with a point where the outer contour of the flexible circuit board changes angle close to the endpoint and located on one side of the differential signal line; the endpoints on the other side of the segment of the routing corresponding to the two differential signal lines each form another boundary of the reference area with a point where the outer contour of the flexible circuit board changes angle close to the endpoint and located on one side of the differential signal line.

7. The method according to claim 5, characterized in that After setting the angle of the grid according to the reference line, the method further includes: setting the position of the grid according to the reference line, specifically including: If the reference line is a differential signal line, the vertical projection of a diagonal line of the grid is made to coincide with the extension direction of the intermediate axis of the differential signal line; otherwise, the vertical projection of a diagonal line of the grid is made to coincide with the extension direction of the reference line.

8. The method according to claim 1, characterized in that The preset length is determined by the speed of the signal transmitted in the routing and the rise time of the signal transmitted.

9. The method according to claim 1, characterized in that: Determining the number of segments included in the routing specifically includes: taking one end of the routing as a starting point, and based on a change in routing direction, determining that the routing is a different segment before and after the direction change.

10. The method according to any one of claims 1 to 9, characterized in that: After setting the angle of the grid according to the routing, the method further includes: On the grid stratum, a third copper wire is arranged in a reference area corresponding to the segment of the routing line located in the corner area of ​​the flexible circuit board, and a vertical projection of the third copper wire coincides with the segment of the routing line.

11. The method according to any one of claims 1 to 9, characterized in that: The first direction is perpendicular to the second direction.

12. The method according to any one of claims 1 to 9, characterized in that: The routing layer includes a copper grid, and the copper grid avoids the routing.

13. The method according to claim 12, characterized in that The position and direction of the grid copper are consistent with the position and direction of a grid formed by the intersection of the first copper wire and the second copper wire at a perpendicular corresponding position.

14. A system for improving the signal integrity of a flexible circuit board, characterized in that: The flexible circuit board includes: a grid layer and a routing layer distributed in the longitudinal direction; the routing layer includes at least one routing line; the grid layer includes a plurality of first copper wires and a plurality of second copper wires, the plurality of first copper wires are parallel to each other in a first direction, the plurality of second copper wires are parallel to each other in a second direction, and the plurality of first copper wires intersect with the plurality of second copper wires to form a plurality of grids; The system comprises: a segment number determination module, which is used to determine the number of segments included in the routing, and there is an angle change between adjacent segments; A grid angle setting module, which is used to set the angle of the grid according to the routing; it specifically includes: A preset angle value judgment module, which is used to judge whether the angle change between adjacent segments of the routing exceeds a preset angle value; A first setting module, which is used to determine the longest segment of the routing line when the angle change between adjacent segments of the routing line does not exceed a preset angle value, and set the angle of the grid in the reference area of ​​the routing line according to the angle of the segment; A second setting module, which is used to set the angle of the grid according to the relationship between the length of the route and the preset length and the route when the angle change between adjacent segments of the route exceeds a preset angle value; The angle of the grid is set according to the angle of the segment in such a way that the extension direction of a diagonal line of the grid is consistent with the extension direction of the segment.

15. An electronic device, characterized in that: include: processor; and, a memory for storing processor-executable instructions; The processor implements the steps in the method of any one of claims 1-13 by running the executable instructions.

16. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the steps in the method according to any one of claims 1 to 13 are implemented.

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