JP2000293565A - Apparatus and method for generating pattern cut diagram of printed circuit board - Google Patents

Abstract

(57) [Summary] [Problem] In a conventional pattern cut position determination system,
Since no noise countermeasure processing is taken into consideration, there is a case where a correct operation cannot be obtained due to noise in an actual remodeled board even though a pattern is cut and a logically correct connection is made. Kind Code: A1 When determining a pattern cut position, it is determined whether or not noise suppression processing should be performed in advance on a section where pattern cutting is necessary, based on the type of signal passing through the remaining pattern after pattern cutting and the length of the remaining pattern. If noise suppression processing is required, the number of pattern cuts is automatically changed from one to a plurality of cuts, and noise suppression is performed in advance in the pattern cut position determination stage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for generating a pattern cut diagram for remodeling a printed circuit board due to a design change, and more particularly to a pattern cut diagram capable of coping with high-speed signal wiring susceptible to electric noise. It relates to a generating device.

[0002]

2. Description of the Related Art There are many expensive electronic components used in transmission devices and the like. To change the function of a prototype printed circuit board on which the electronic components are mounted, pattern cutting and jumper wire connection are performed. Regarding the automatic generation of the pattern cut diagram of the pattern cut, a method of automatically determining the pattern cut position from the connection section information of the component pin requiring the pattern cut and generating the pattern cut diagram has been proposed. In connection with this proposal, Japanese Unexamined Patent Publication No.
JP-A-4-32696, JP-A-3-246679, and JP-A-4-21074.

[0003]

The above prior art focuses only on determining a pattern cut position after extracting a section requiring a pattern cut due to a change in a logical connection accompanying a design change. As a countermeasure against electric noise received by the remaining pattern afterward and further by component pins connected to the remaining pattern, electric conditions such as shortening the remaining pattern as much as possible are not considered. For this reason, there is a problem that a correct operation may not be obtained due to noise in an actual remodeled board despite the fact that a logically correct pattern cut is performed.

An object of the present invention is to provide a countermeasure in advance in consideration of electric noise received by component pins connected to a remaining pattern after pattern cutting when determining a pattern cut position. To prevent the pattern cutting from being performed.

[0005]

In order to achieve the above-mentioned object, when a pattern cut position is determined, a pattern cut is required depending on the signal type of the section requiring the pattern cut and the length of the remaining pattern after the pattern cut. It is determined in advance whether or not noise processing should be performed. As a result, when the noise countermeasure processing is required, the pattern cut is automatically performed once or plural times in one section connecting the component pins so as to shorten the remaining pattern from the component pins. To do.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a pattern cut diagram generating apparatus according to an embodiment of the present invention will be described below with reference to FIGS.

First, an overall configuration of a pattern cut diagram generating apparatus will be described with reference to FIGS. Here, FIG. 4 is a block diagram of the pattern cut diagram generation device. FIG. 6 is an external view of a pattern cut diagram generating apparatus.

The pattern cut diagram generating apparatus inputs pattern data 41 before remodeling and latest logical connection data 42 incorporating design changes, and a remodeling difference extracting unit 43 specifies a pattern to be cut and a jumper wiring pattern. The route to be extracted is extracted, and the information is passed to the remodeling data editing unit 44. The remodeling data editing unit 44 passes these data to the remodeling data automatic determination unit 45 or the remodeling data dialogue determination unit 46, captures the determined pattern cut position and jumper wiring path, merges the results, and merges the results to obtain the remodeling data result. Output to file 47.

The pattern cut position and the jumper wiring path are determined by interactively indicating some of the pattern cut positions or the jumper wiring paths on the pattern displayed on the screen by the remodeling data dialogue determination unit 46, and then the remaining data is obtained. The data is passed to the remodeling data automatic determination unit 45 for the minute, and the remodeling data automatic determination unit 45 refers to the cutting condition 4A, the component information 4B, and the net attribute information 4C to automatically determine the pattern cut position and the jumper wiring path. be able to. Conversely, the pattern cut position and the jumper wiring path determined by the remodeling data automatic determination unit 45 are changed to the remodeling data dialogue determination unit 4.
It is also possible to correct at 6.

The remodeling data such as pattern cuts and jumpers created in this way are output to a remodeling data result file 47, and a remodeling drawing output unit 48 outputs a work instruction drawing 49 for pattern cutting and jumper wiring.

The automatic generation of the pattern cut in consideration of the noise countermeasure is incorporated in the pattern cut position determination processing 452 in the remodeling data automatic determination unit 45 and the pattern cut position input processing 463 in the remodeling data dialogue determination unit 46. Used.

FIG. 6 shows an external view of a pattern cut diagram generating apparatus. The pattern cut diagram generating apparatus includes an input display unit 61, a print output unit 62, a CPU 63, an external memory 64, an internal memory 65, and a wiring pattern data 641, a component information 642, as in a normal computer. , Net attribute information 643, and logical connection data 644. Functions such as remodeling difference extraction, remodeling data dialogue determination, remodeling data automatic determination, and remodeling data editing shown in FIG. The operation is realized by the CPU 63 by the operation from the input display unit 61.

Hereinafter, a procedure for automatically generating a pattern cut in consideration of noise countermeasures will be described with reference to FIGS.

Embodiment 1 FIG. 1 shows a flowchart of a pattern cut generation process in which noise measures are taken into consideration. FIG. 2 is a diagram illustrating a rule for determining an allowable remaining pattern length of a pattern cut for determining whether noise countermeasures are necessary, and FIG. 3 is a plan view illustrating a process of generating a pattern cut. First, in step 11 of FIG. 1, it is determined whether there is a short-circuited wiring pattern. Next, the nets (net 1 and net 2) of the short-circuited wiring pattern and the attribute information of the nets in steps 12 to 13 are extracted. These steps are processing until the information extracted by the remodeling difference extracting unit 43 in FIG. 4 is passed to the remodeling data automatic determination unit 45 via the remodeling data editing unit 44. Here, the attribute information means, for example, an electric level, a signal type, and an operating frequency.

Table 21 in FIG. 2 is a table showing the allowable remaining pattern length for each net attribute.
Classification of electrical levels such as L, ECL, etc., signal type 212 classifies data, clocks, etc., operation frequency 213 classifies differences in operation speed, and from these combinations, the allowable remaining pattern length 214 is determined. It is a table. In the case of a combination that is not specified in this rule, the allowable remaining pattern length is set to infinity, and this value makes it possible to determine that the effect of noise will not be affected no matter how long the remaining pattern length becomes in a later step. Used for Table 22 in FIG. 2 is a table showing attribute information of the nets on the printed circuit board.
Electric level 222, signal type 223, operating frequency 224
Is defined.

Returning to FIG. 1, step 14 and step 1
5, the electric level 22 of each net is shown in Table 22 of FIG.
2, the net attribute of the signal type 223 and the operating frequency 224 are extracted, and the attribute of the extracted net is shown in Table 21 of FIG.
, The corresponding remaining pattern length 214 is extracted. At this time, the allowable remaining pattern length of the net 1 is A, and the allowable remaining pattern length of the net 2 is B. In this example, Table 22 in FIG.
In Table 21, A is LT1 and B is LT3. Next, at step 16, the value obtained by adding A and B is set as LT.

Next, in step 17, the length of the short wiring pattern (hereinafter referred to as a required pattern cut segment) is extracted, and the length is set to L. Hereinafter, the required pattern cut segment refers to a net element that needs to be cut in order to cut a net element such as a pin or a via belonging to one net into a plurality of nets by remodeling. FIG.
In the example of FIG. 3, the pin 32 of the component 31 and the pin 34 of the component 33 are the same net 0 (FIG. 3A).
As shown in (b), the pin 3 of the component 31 is changed by the logical change.
The pattern 35 connecting the pin 32 and the pin 34 when the pin 2 of the component 33 is changed to the net 1 and the pin 34 of the component 33 is changed to the net 2 corresponds to the required pattern cut segment.

Next, at step 18, LT is compared with L. As a result, if LT is larger than L,
9 and if LT is less than or equal to L, the process proceeds to step 1A.
In the case of FIG. 3, since LT is larger than L, step 19
The section 38 where the section 36 from the component pin 32 to the allowable remaining pattern length of the net 1 overlaps the section 37 from the component pin 34 to the allowable remaining pattern length of the net 2 (FIG. 3)
In FIG. 3D, the pattern cut position 39 is determined (FIG. 3).
(E)). The cut position determination method is determined by, for example, an automatic pattern cut position search by a method that considers a part or the like as an obstacle. Next, returning to step 11, when all the pattern cut positions are determined, the obtained pattern cut position 39 is passed to the remodeling data editing unit 44 in FIG. 4 and output to the remodeling data result file 47. Finally, the modified drawing output unit 48 outputs a drawing for instructing the pattern cutting position.

If the process proceeds from step 18 to step 1A (FIG. 3 (c) '), a cut position 3C is determined from the pin 32 to a section 3A corresponding to the allowable remaining pattern length of the net 1 (FIG. 3 (d)). ') Further, a cut position 3D is determined from the pin 34 to a section 3B corresponding to the allowable remaining pattern length of the net 2 (FIG. 3 (e)'). As in step 19, the cut position is determined by an automatic pattern cut position search.

Next, returning to step 11, when all the pattern cut positions are determined, the obtained pattern cut positions 3C and 3D are passed to the remodeling data editing unit 44 in FIG. 4 and output to the remodeling data result file 47. . Finally, the modified drawing output unit 48 outputs a drawing for instructing the pattern cutting position.

Embodiment 2: In the example of the pattern cut shown in FIG. 3, an embodiment in which the pattern cut position is determined by an operator's interactive input will be described.

In FIG. 1, the short wiring pattern is extracted in step 12, the attribute of the shorted net is extracted in step 13, the allowable remaining pattern length of net 1 is extracted in step 14, the allowable remaining pattern length of net 2 is extracted in step 15. The addition of the allowable remaining pattern lengths of the nets 1 and 2 in step 16 and the calculation of the allowable remaining pattern length in step 17 are automatically performed in the same manner as in the previous embodiment.

After extracting the short-circuited wiring pattern (required pattern cut segment) 35 in step 12, the remodeling data dialogue determination section 46 inputs the input display section 6.
By changing the display color, line thickness, blinking display, and other display attributes of the required pattern cut segment 35 to 1, the interactive operator can easily input a pattern cut position from the input display unit 61. I do. Next, as in the above-described embodiment of the automatic determination, the pattern cutting process is sequentially performed on the nets 1 and 2 of both the pins 32 and 34.

At this time, if it is necessary to further determine the pattern cut position for noise suppression in the net 1 or the net 2, the remodeling data dialogue determination section 46 prompts the dialogue operator to input the pattern cut position. For example, FIG.
In the example of (d) ′, consider a case where the cut position 3C is determined by an interactive operation. Since the remaining pattern from the component pin 34 to the cut position 3C in the net 2 exceeds the allowable remaining pattern length LT3, it is necessary to interactively input a pattern cut position for noise suppression. At this time, by displaying the remaining pattern with the display attribute changed similarly to the display of the pattern cut segment, the interactive operator can easily input the pattern cut position from the input display unit 61. Also, the pattern cut position 3D input interactively
If the remaining pattern length exceeds the allowable remaining pattern length, the remaining patterns are displayed with different display attributes, and the user is prompted to re-enter the pattern cutting position until a pattern cutting position that satisfies the conditions is input. Prompt the operator (if the pattern cut position is input again, the previous pattern cut position is discarded). In this way, the pattern cut position is determined for the first time when the pattern cut position satisfying the condition is input, and the process proceeds to the next step.

Other processes are the same as those in the above-described embodiment of automatic determination.

Embodiment 3 Referring to FIGS. 1 and 5, a description will be given of a processing procedure for automatically determining a pattern cut position in consideration of a countermeasure against noise when a pattern branches into three.

First, the wiring pattern 58 short-circuited in step 12 is taken out in the same procedure as in the first embodiment.
In the example of FIG. 5, the pin 56 of the component 55 belongs to one of the modified nets (net 1), and the pin 52 of the component 51, the pin 54 of the component 53, and the via 57 are connected to the other modified net (net 2). 5), in order to divide the net 1 and the net 2, it is necessary to find the pattern cut position on the pattern 58 as shown in FIG. At step 13, the attributes of the connected nets (net 1 and net 2) are extracted. At step 14, net 1 indicated by 5A
In step 15, an allowable remaining pattern length LT1 of net 2 indicated by 59 is extracted. In step 16, a value LT obtained by adding the allowable remaining pattern lengths of net 1 and net 2 is calculated. Short wiring pattern at 17 (pattern cut segment required) 5
8 is calculated.

Next, at step 18, as shown in FIG. 5C, the length LT3 of the section 5A corresponding to the allowable remaining pattern length of the net 1 from the pin 56 and the allowable remaining pattern length of the net 2 from the via 57 are determined. LT of the length LT1 of the section 59 of
When the length L of the required pattern cut segment 58 is compared with L, the length L is larger than LT, so that the length of the allowable remaining pattern length of the net 1 and the net 2 overlaps with the pattern section 5B (FIG. 5D). , The cutting position 5C is determined (FIG. 5E). The cut position determination method is determined by an automatic pattern cut position search, as in the first embodiment.

Next, in step 11, since all the pattern cut positions have been determined, the obtained pattern cut position 5C is passed to the remodeling data editing unit 44 in FIG. Output. Finally, the modified drawing output unit 48 outputs a drawing for instructing the pattern cutting position.

[0030]

According to the present invention, it is possible to prevent a rework such as taking noise countermeasures for a pattern in which a problem has occurred, after testing a modified printed circuit board on which a pattern has been cut in an actual machine. Further, since the pattern cut position for noise suppression is automatically obtained, the remodeling designer does not need to manually examine where to cut the pattern.

Further, since an additional pattern cut instruction for noise suppression is output only when necessary, it is possible to prevent an unnecessary increase in the number of pattern cutting steps due to unnecessary noise suppression.

[Brief description of the drawings]

FIG. 1 is a flowchart of a pattern cut generation process in which noise suppression is considered according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an allowable remaining pattern length reference and attributes of each net according to an embodiment of the present invention.

FIG. 3 is a plan view illustrating a process of generating a pattern cut according to an embodiment of the present invention.

FIG. 4 is a block diagram of a pattern cut diagram generating apparatus according to an embodiment of the present invention.

FIG. 5 is a plan view illustrating a process of generating a pattern cut according to an embodiment of the present invention.

FIG. 6 is an external view of a pattern cut diagram generation apparatus according to an embodiment of the present invention.

[Explanation of symbols]

31: a component 1 having a pin connected to the net 1 by a logical change from the net 0; 32: a pin 1 connected to the net 1 by a logical change from the net 0; 33: a pin connected to the net 2 by a logical change from the net 0 Parts 2 and 3
4 ... Pins 2 and 35 connected to Net 2 by logical change from Net 0, 35 ... Short wiring pattern, L ... Pattern length of required pattern cut segment, 36 ... Section of allowable remaining pattern length of Net 1, 37 ... Net 2 The section corresponding to the allowable remaining pattern length, LT1... The allowable remaining pattern length of the net 1, LT3... The allowable remaining pattern length of the net 2, 38. Overlapping section, 39... Mark indicating pattern cut position in consideration of noise suppression, 3A... Another example of allowable remaining pattern section of net 1, 3B.
, LT1 ′..., LT1 ′..., Another example of a section corresponding to the allowable remaining pattern length of the net 1, LT3 ′.
The length of another example of the section corresponding to the allowable remaining pattern length of the net 2,
3C: mark indicating a cut position in consideration of noise countermeasures on the net 1 side; 3D: mark indicating a cut position in consideration of noise countermeasures on the net 2 side; 41: pattern data before remodeling; 42: latest logical connection data; Modification difference extraction unit, 44: Modification data editing unit, 45: Modification data automatic determination unit, 46: Modification data dialogue determination unit, 47 ...
Remodeling data result file, 48 ... Remodeling drawing output part, 4A
... Cutting condition, 4B. Component information, 4C. Net attribute information, 51. Component 1 having pin 1 connected to net 2 by logical change from net 0, 52. Pin 1 connected to net 2 by logical change from net 0 53, a component 2 having a pin 2 connected from the net 0 to the net 2 by a logical change, 54 a pin 2 connected from the net 0 to the net 2 by a logical change, 55 ... a pin 3 connected from the net 0 to the net 1 Parts 3, 56 having pins 3, 57 which are connected to net 1 by a logical change from net 0, vias which are connected to net 2 by a logical change from net 0, 58 ... pattern cut segment required, L: pattern of required pattern cut segment Length, 59: Section for the allowable remaining pattern length of Net 2; 5A: Section for the allowable remaining pattern length of Net 1; 5B: Net 1 Overlapping portions of Residual pattern length minute intervals and Residual pattern length fraction section of the net 2, 5C
... A mark indicating a pattern cut position, 61... An input display section, 62... A printing section, 63... A CPU, 64. An external memory, 65. An internal memory, 641. 6
44: logical connection data, 645: cut condition information.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiro Aono 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Communication Systems Division of Hitachi, Ltd. (72) Inventor Seiichi Nakakuma Onoe-cho, Naka-ku, Yokohama-shi, Kanagawa 6-81 Hitachi Software Engineering Co., Ltd. In-house (72) Inventor Yuichi Soejima 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Co., Ltd. Communication Systems Division, Hitachi, Ltd. (72) Inventor Shigeki Tsukada Totsuka-ku, Yokohama-shi, Kanagawa 216 Totsukacho, Hitachi, Ltd. Communication Systems Division, Hitachi, Ltd. (72) Inventor Keiichi Saito 216, Totsukacho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture F-term in Hitachi, Ltd. Communication Systems Division 5B046 AA08 BA04 DA00 GA01 HA09 JA01 5E343 ER51 FF30

Claims (5)

[Claims] 1. A pattern cut diagram generating apparatus for inputting pattern information and logical connection information of a printed circuit board, extracting whether a pattern between component pins of the printed circuit board requires cutting, determining a position of the pattern cut, and outputting the cut pattern. A pattern cut diagram generation apparatus for a printed circuit board, wherein a noise suppression factor is determined in accordance with a signal type of a pattern cut section, and a pattern cut position and a number of pattern cuts for noise suppression are automatically determined. 2. The pattern cut diagram generating apparatus according to claim 1, wherein a plurality of pattern cut positions are designated in one pattern cut section. 3. The pattern cut diagram generating apparatus according to claim 1, wherein a noise countermeasure factor is determined according to a signal type of a wiring pattern cut section, and a pattern cut position and a number of pattern cuts for the noise countermeasure are automatically determined. And a means for displaying a pattern requiring a new pattern cut by changing attributes such as a display color and a line thickness, and a means for an operator to interactively input a pattern cut position. Pattern cut diagram generation device for printed circuit boards. 4. A step of inputting mounting pattern information and logical connection information of a printed board, extracting whether a pattern cut is required between a plurality of component pins of the printed board, and determining a position of the pattern cut. Determining a pattern cut position for noise suppression in accordance with the signal type of the pattern; specifying a pattern cut position in accordance with the determination result; and outputting the result as a drawing. Method for generating a pattern cut diagram of a printed circuit board. 5. The method of generating a pattern cut diagram according to claim 4, wherein the step of determining a pattern cut position for noise suppression according to a signal type of the pattern comprises:
Means for measuring the length of a pattern (hereinafter referred to as a residual pattern) from a component pin to a pattern cut candidate position;
It is necessary to have means for determining the length of the remaining pattern allowed in each net after the pattern cut (hereinafter referred to as allowable remaining pattern length) and means for determining the pattern cut position by comparing the remaining pattern length with the allowable remaining pattern length. A method for generating a pattern cut diagram of a printed circuit board which is a feature.