JPH0636014B2 - Circuit network search device - Google Patents

Description

The present invention relates to a circuit net search device, and in particular, it is used for obtaining information necessary for a resistance test for inspecting normality / abnormality of a wiring pattern formed on a printed circuit board. Circuit network search device.

[Technical environment]

In recent years, printed circuit boards have tended to be large-sized, highly densified, and multi-layered, and accordingly, wiring patterns formed of conductors on printed circuit boards have tended to be finer, more complicated, and longer in length.

On the other hand, since the wiring pattern formation technology is not perfect, abnormalities such as erroneous connection (short circuit) between wiring patterns and disconnection (open) of wiring patterns still remain, and how to discover this It's a big problem.

Conventionally, a human being visually inspects a wiring pattern for normality / abnormality. However, due to the thinning and complexity of the wiring pattern described above, a printed circuit board that exceeds human ability appears and a machine that replaces the visual inspection is used. Electrical inspection has become an important tool.

There are various methods for electrical inspection, but among them, the electrical resistance between two end points that belong to one continuous wiring pattern called a circuit net is measured and compared with a logical resistance value to judge the correctness of the circuit net. Resistance test is effective. The reason is that the principle is simple, that the measurement accuracy is good, and that an abnormal place is easy to find.

However, in the resistance test, since the logical value of the resistance is required, it must be clarified because one end point and the other end point are connected through which route in the circuit net. The circuit net search device is necessary for this purpose.

[Conventional technology]

FIG. 2 is a plan view showing an example of a circuit net formed on a printed circuit board. Generally, many circuit nets are formed on the printed circuit board, but for the sake of simplicity, FIG. 2 shows an example in which only one circuit net 15 is formed on the printed circuit board 14. 12A to 12G are end points of the circuit net 15, and 11A to 11K are branches forming the circuit net 15 (wiring elements between end points or branch points).
Is. 13A to 13E are branch points that represent branch branches.

In the conventional circuit net search device, when the starting point serving as the reference of measurement when the resistance inspection of the circuit net 15 is performed is the end point 12A, the end point 12A and the end points 12B connected thereto,
It only outputs each combination of 12C, 12D, 12E, 12F and 12G.

[Problems to be Solved by the Invention]

As described above, the conventional circuit net search device merely outputs the distinction of connection / non-connection between two points,
It was not possible to clarify the connection state of the branches forming the circuit net, and it was not possible to calculate the logical value of the resistance between the two points to be measured from the results. Therefore, in the conventional resistance test, if the resistance between two points in the same circuit net is infinite, a disconnection is made, and if the resistance between two points belonging to different circuit nets is a finite value, only a large test is performed. could not.

For this reason, it is necessary to compare with the logical value of the resistance.
It was not possible to realize an accurate inspection to detect "thin" wiring patterns or incomplete connections.

An object of the present invention is to eliminate the above-mentioned drawbacks and to provide a circuit net search device capable of outputting connection route information between two points.

[Means for Solving the Problems]

A circuit net search device of the present invention is a circuit net search device that searches for connections of circuit nets formed on a printed circuit board, and a branch connection storage unit that stores a connection state of branches that form the circuit net, and the circuit. A branch search storage unit that stores a search state of a branch at each point during the search of the net, and a start branch and a terminal branch of the circuit net by inputting data in the branch connection storage unit and the branch search storage unit. And a search unit that outputs branch route data that connects the branch route, and the search storage unit sequentially stores a self-branch being searched and a parent branch connected to the start branch side of the self-branch as a pair. The structure includes an open stack and a path stack of a stack structure that stores a list of branches that are connected to each other in the order from the start branch to the self branch, and the search unit includes a start branch that is the start point of the search. Detected and A start branch detecting unit that pushes to the bottom of the pun stack and the path stack, and whether the top of the open stack is the end branch, and if it is the end branch, the contents of the path stack at that time are branch paths. End branch detection means for outputting as data, thereafter discarding the head of the open stack, and updating the contents of the path stack to represent the path to the head branch of the open stack; and the head of the open stack ends. When the branch is not a branch, it is configured to include a branch branch expansion unit that replaces the list of branches branched from the branch with the head of the open stack.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

The circuit net search device shown in FIG. 1 includes a branch connection storage unit 1 that stores connection information of branches that form a circuit net, and a branch search storage unit that stores a branch search state at each time point during the search of the circuit net. 2 and a search unit 3 that performs actual search processing using the data of the branch connection storage unit 1 and the branch search storage unit 2,
The search result is output as route data 4. The branch search storage unit 2 includes an open stack 5 and a path stack 6, and the search unit 3 includes a start branch detection unit 7, an end branch detection unit 8, and a branch branch expansion unit 9.

To summarize the function of the present invention, the branch connection storage unit 1 stores a plurality of sets of branch name of a branch forming a circuit net, and this information is used as an input to configure the branch search storage unit 2. Using the open stack 5 and the route stack 6 as a working storage device, the search unit 3 outputs the branch connection route information connecting the start branch of the circuit net and all the end branches as the route data 4.

The details will be described below with reference to FIG. The branch connection storage unit 1 includes a branch 1 that constitutes a circuit net 15.
The connection information of 1A to 11K is stored, and this is input. If the end point 12A of the circuit net 15 is the starting point, the branch 11A is the starting branch. When the search unit 3 operates,
The output first shows (11A, 11B, 11C, 11D,
11E) is obtained as the route data 4. In other words, the branch connection route information connecting the start point 12A and the end point 12B is obtained. In this case, the terminal branch is 11E. Similarly, for the terminal point 12C, (11A, 11B, 11
C, 11D, 11F) is (1
1A, 11B, 11C, 11D) and (11A, 11I, 11K) are output as the route data 4 to the terminal point 12G. 6 in total corresponding to the terminal points 12B to 12G
The set is output as the route data 4.

Hereinafter, operations of the branch connection storage unit 1, the branch search storage unit 2, and the search unit 3 will be described in detail.

FIG. 3 is a detailed configuration diagram of the branch connection storage unit 1. As shown in FIG. 2, the branch 11A connected to the end point 12A is connected to the branch 11B and the branch 11I. The pair of branch names (11A, 11B) and (11A,
11I) is stored in the branch connection storage unit 1 as a branch connection pair. Hereinafter, all branch connection pairs included in the circuit net 15 and having a connection relationship are stored in the branch connection storage unit 1. There are various possible arrangement orders of the branch connection pairs, but here, in order to simplify the description, the arrangement order of the branch connection pairs is closer to the branch 11A. FIG. 3 shows a set of branch connection pairs having the end point 12A as the starting point for the circuit net 15 shown in FIG. 2, but a set of branch connection pairs having the other end points 12B to 12G as the starting points. You may store it. These can be created in advance from the connection information of the circuit net 15 including the branch points 13A to 13E.

FIG. 4 is a detailed configuration diagram of the open stack 5. In this stack, each item is composed of two elements, a self branch name 31 and a parent branch name 32. The branch that is about to be handled is the self branch, and the branch connected to the self branch is the parent branch that is closer to the start branch. For example, it can be seen from FIG. 2 that the parent branch of the branch 11H is 11B.

FIG. 5 is a detailed configuration diagram of the path stack 6. In this stack, each item is composed of only one element of the path branch name 41, and the row of branch names from the bottom to the top of the stack represents the path from the start branch to the currently handled branch. .

FIG. 6 is a block diagram for explaining the operation of the start edge detection unit 7. The start branch detecting unit 7 detects a start branch from the branches stored in the branch connection storage unit 1. As a detection method, the branch connection pair shown in FIG. 3 may be searched for the one that appears only in the left term and used as the start branch. Therefore, the starting branch is 11A
become. When the starting branch is found, it is pushed to the bottom of the open stack 5 and the path stack 6. Since there is no parent branch of the start branch, nothing is entered in the parent branch name of the open stack 5.

FIG. 7 is a flow chart showing the flow of the operation of the terminal edge detection unit 8, and FIG. 9 is a block diagram for explaining the operation of the terminal edge detection unit 8.

First, the terminal branch detection unit 8 confirms whether the open stack 5 is empty. If it is empty, it ends there (S
101).

Next, it is confirmed whether or not the name of the first branch of the open stack 5 is the end branch (S102). Open stack 5
If the leading self-name of the branch is not the end branch, the branch is a branch branch, so the branch branch signal 10 is output, the branch branch expansion unit 9 is operated (S107), and the end is waited (S107).
108). Whether or not the branch is a terminal branch can be determined by whether or not the branch in question appears in the left side term of the branch connection pair forming the branch connection storage unit 1. Open stack 5 in the example of FIG.
Since the self branch name at the head of a is 11E, as can be seen from FIG. 3, this does not appear in the item on the left side of the branch connection pair. Therefore, it is a terminal branch.

If it is the terminal branch, the contents of the route stack 6 at that point are directly output as the route data 4 (S10).
3). Then, the top of the open stack 5 is discarded (S
104). In the example of FIG. 8, the first item (self-branch name 11E, parent-branch name 11D) is discarded and it becomes an open stack 5b.

Subsequently, the same route branch name as the leading parent branch name of the open stack 5 is searched from the route stack 6, and a portion shallower than this route branch name is discarded from the route stack 6 (S105). Then, the head self-name of the open stack 5 is pushed onto the path stack 6 (S106). In the example of FIG. 8, since the leading parent branch name of the open stack 5b is 11D,
By step S105, a portion shallower than the route branch name 11D in the route stack 6a, that is, 11E is discarded.
Since the self-branch name at the head of the open stack 5b is 11F, 11F is pushed to the head of the path stack 6 in step S106, resulting in the path stack 6b.
The results shown in are obtained.

FIG. 9 is a block diagram for explaining the operation of the branch branch expansion unit 9. As described above, the branch-branch expanding unit 9 is activated by the branch-branch signal 10 when the head self-branch name of the open stack 5 does not represent the terminal branch. The branch branch expansion unit 9 refers to the branch connection storage unit 1 and refers to the branch name (there may be a plurality) branching from the branch represented by the head self-name of the open stack 5,
Replace the self-branch name at the top of the open stack 5. The leading parent branch name of the replaced new open stack 5 is the previous leading branch name. Then, the head self-name of the open stack 5 is pushed onto the path stack 6.

In this embodiment, the branch branching from the branch represented by a certain branch name is the branch on the left side of the branch connection pair in the branch connection storage unit 1 on the right side of all branch connection pairs having the same branch name. It can be obtained by extracting. When there are a plurality of branching branches, the branching branch names are sorted in descending order, and the top of the open stack 5 is replaced in the sorted order.

In the example shown in FIG. 9, the self-branch name at the head of the open stack 5c is 11A, so when looking at the branch connection storage unit 1,
There are two that have 11A in the left-hand term of the branch connection pair.
Since the items on the right side of these branch connection pairs are 11B and 11I, these are the self-branch names, and the parent branch name is the previous self-branch name 11
The head of the open stack 5c is replaced with the item A. When replacing, the branch branch names are sorted in descending order, and thus are pushed in the order of 11I and 11B. As a result, the open stack 5d shown in FIG. 9 is obtained. Since the head branch name 11B of the open stack 5d is pushed onto the route stack 6c, the result of the route stack 6d is obtained.

FIG. 10 is a state transition diagram when the entire processing of the above embodiment is applied to the circuit net 15 shown in FIG. The term of time represents the time when the state of this embodiment changes.

First, at time 0, the start branch detection unit 7 is activated as described above, and the start branch name 11A is pushed to the open stack own branch name and the path stack. Since the self branch name 11A at the head of the open stack is not the end branch, time 1
Is raised by the branch branch expansion unit 9, and 11I and 11B are entered in order from the bottom in the self-branch name of the open stack,
11B is pushed onto the path stack.

Similarly, only the replacement process is performed until time 3.

At time 4, the leading branch name 11E of the open stack is determined by the trailing edge detection unit 8 to be the trailing edge. At this time, the contents of the path stack (11A, 11B,
11C, 11D, 11E) is output as route data. Then, the top of the open stack is discarded, and the contents of the path stack are updated accordingly.

Similarly, the operation of the branch branch expansion unit 9 described in detail above outputs the route data at times 5, 6, 7, 9, and 10. Finally, at time 10, the open stack's own branch name is 1
It becomes 1K and is discarded because it is a terminal branch.
At 1, the open stack is empty. The terminal edge detection unit 8 detects this and ends the search processing of this circuit net.

〔The invention's effect〕

As described in detail above, the circuit net search device of the present invention searches the entire circuit net and outputs not only the start point and the end point belonging to the circuit net, but also the branch connection path information connecting the start point and the end point. Therefore, there is an effect that it is possible to create accurate data for resistance inspection.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a plan view showing an example of a circuit net handled by the present invention, FIG. 3 is a detailed configuration diagram of a branch connection storage unit shown in FIG. Figure 4 shows the first
The detailed configuration diagram of the open stack shown in the figure, and FIG.
6 is a detailed configuration diagram of the path stack shown in FIG. 6, FIG. 6 is an operation block diagram of the start branch detection unit shown in FIG. 1, FIG. 7 is a flow chart of the schematic operation of the end branch detection unit shown in FIG. 1, and FIG. Is an operation block diagram of the terminal branch detecting unit shown in FIG. 1, and FIG. 9 is an operation block diagram of the branch branch expanding unit shown in FIG.
The figure is a state transition diagram of an embodiment of the present invention. 1 ... Branch connection storage unit, 2 ... Branch search storage unit, 3 ... Search unit, 4 ... Route data, 5 ... Open stack, 6 ...
... Path stack, 7 ... Starting branch detecting section, 8 ... Ending branch detecting section, 9 ... Branch branch expanding section, 10 ... Branch branch signal, 11
A-11K ... Branch, 12A-12G ... End point, 13A-
13E ... branch point, 14 ... printed circuit board, 15 ... circuit net.

Claims (1)

[Claims] 1. A circuit net search device for searching for a connection of a circuit net formed on a printed circuit board, and a branch connection storage unit storing a connection state of a branch forming the circuit net, and a circuit net being searched for. A branch search storage unit that stores a search state of a branch at each time point, and a branch that connects a start branch and an end branch of the circuit net by inputting data in the branch connection storage unit and the branch search storage unit. An open stack having a stack structure that includes a search unit that outputs route data, wherein the search storage unit sequentially stores a self-branch under execution of a search and a parent branch connected to a start branch side of the self-branch as a pair. And a path stack of a stack structure that stores a list of branches that are connected to each other in the order from the start branch to the self branch, wherein the search unit detects the start branch that is the start point of the search and opens the open branch. Stack and Start branch detection means for pushing to the bottom of the path stack and whether the top of the open stack is the end branch, and if it is the end branch, the contents of the path stack at that time are output as branch path data. And then discarding the head of the open stack and updating the contents of the path stack so as to represent the path to the head branch of the open stack; and the case where the head of the open stack is not the end branch. And a branch branch expanding means for replacing a list of branches branching from the branch to the head of the open stack.