JP2003288381A - Method and device for verifying crosstalk noise quantity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for verifying the quantity of crosstalk noise capable of measuring quantity of the crosstalk noise of a signal extending over a plurality of wiring board, when constructing one system by the plurality of wiring boards, by making the noise margin of signal extending over the plurality of wiring boards appropriate to enable a design adaptable to high-speed signal. <P>SOLUTION: The connecting relation of networks 11 and 21 on the plurality of wiring boards 1 and 2 to be connected through connectors is detected based on the position information of networks 11, 16, 21 and 26 on the wiring boards 1 and 2 and the connecting relation of the connectors 4 and 5 for connecting the wiring boards 1 and 2 to calculate how each network 11, 21 receives noise quantity from the peripheral networks 16 and 26 on each wiring board 1, 2. In reference to the above connecting relation, the noise quantity every wiring board 1, 2 is added with respect to the networks 11, 21 and it is judged whether the noise quantity on a network consisting of the networks 11 and 21 is within an allowable range or not. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crosstalk noise amount verification method and device, and more particularly to a crosstalk noise amount verification method and device for verifying the crosstalk noise amount of a signal across a plurality of wiring boards.

[0002]

2. Description of the Related Art Conventionally, when designing wirings for a plurality of wiring boards, an upper limit of crosstalk noise amount is set for each wiring board, and wiring designing is performed so as not to exceed the upper limit. A crosstalk amount verification method performed for each wiring board is disclosed in, for example, Japanese Unexamined Patent Publication No. 2-238573, a wiring path search apparatus for wiring design of a printed circuit board or the like, in which the selected wiring path is determined by then. Calculate the amount of crosstalk noise given to
There is disclosed a method for evaluating whether or not the total amount of crosstalk noise exceeds a limit value for normal operation of a circuit.

[0003]

However, in the above-mentioned conventional technique, when the wiring is designed so as not to exceed the upper limit of the crosstalk noise amount of each wiring board, for example, the scale of the wiring board connected by the connector is used. If the set value of the crosstalk noise amount is too large due to the difference in the wiring density and the difference in the wiring density, the crosstalk amount of the signal connecting the wiring boards may be exceeded. On the other hand, if it is too small, the noise will be excessively designed, which will hinder proper wiring board mounting design.

An object of the present invention is to optimize a noise margin of a signal across a plurality of wiring boards when constructing one system with a plurality of wiring boards, and to enable a design corresponding to a high-speed signal. Thus, it is an object of the present invention to provide a crosstalk noise amount verification method and device capable of accurately measuring the crosstalk noise amount of a signal across a plurality of wiring boards.

[0005]

The crosstalk noise amount verification method of the present invention is based on the input positional information of the nets on a plurality of wiring boards connected to the connectors and the connection relation of the connectors connecting the wiring boards. Detecting the connection relationship between nets on each wiring board, calculating how much noise each net receives from the surrounding nets on each wiring board, and referring to the connection relationship above, the connected nets For each of the wiring boards, the noise amount for each wiring board is added to determine whether the noise amount on the net formed of the connected nets is within the allowable range.

The crosstalk noise amount verification apparatus of the present invention further comprises an input section for inputting positional information of nets on a plurality of wiring boards to be connected to the connectors and a connection relation of the connectors connecting the wiring boards, and the plurality of the input sections. A net tracking unit that detects the connection relationship between the nets on each wiring board based on the positional information of the nets on the wiring board and the connection relationship of the connectors that connect the wiring boards, and the nets on the wiring board where each net is a peripheral net. Add the noise amount for each wiring board for the connected nets by referring to the wiring board crosstalk calculator that calculates how much noise is received from the wiring board and the connection relationship between the nets on each wiring board And a limit value comparison judgment for determining whether the noise amount on the net formed of the connected nets is within the allowable range. And a part.

According to the present invention, even when a signal is spread over a plurality of wiring boards, the noise amount of each wiring board is added to the nets to be connected, and the noise on the net formed of the connected nets is added. Since it is determined whether the amount is within the allowable range, it is possible to measure an appropriate amount of crosstalk noise and reflect it in the wiring when constructing one system with a plurality of wiring boards. As a result, the noise margin is optimized and high-speed signal design is possible.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, FIG. 1 shows an example of a connector connection substrate which is a noise amount verification target of a crosstalk noise amount verification device of the present invention.

The connector connection board comprises two boards, a wiring board 1 and a wiring board 2. There are connectors 3 and 4 for connecting the wiring board 1 and the wiring board 2.

In the wiring board 1, the pins of the connector 3 and the pins of the parts on the wiring board 1 are, for example, the nets 11 and 1.
2, 13, 14, and 15, and in the wiring board 2, the pins of the connector 4 and the pins of the components on the wiring board 2 are connected by nets 21, 22, 23, 24, and 25. Further, for example, the nets 11, 12, 13, 14, 15 of the wiring board 1 are connected via the connectors 3, 4.
And the nets 21, 22, 23, 24, 2 on the wiring board 2.
5 and 5 are connected to each other.

Further, an electric component 5 is mounted on the wiring board 1, and an electric component 6 is mounted on the wiring board 2. For example, the net 11 is connected to the electric component 5, and the net 21 is the electric component 6.
The net including the net 11 and the net 21 connected to each other serves as an interface signal between the electric components 5 and 6. In the wiring board 1, the net including the nets 11 and 21 receives crosstalk from the net 16 having a wiring portion parallel to the net 11 on the wiring board 1, and in the wiring board 2, on the wiring board 2. Crosstalk noise is received from the net 26 having a wiring portion parallel to the net 21.

Next, the structure of the crosstalk noise amount verification apparatus of the present invention will be described with reference to FIG.

The input section 30 inputs data of the wiring boards 1 and 2 for verifying the amount of crosstalk noise. The data of the wiring boards 1 and 2 is information indicating the type of parts on each wiring board, for example, the types of the electric parts 5 and 6, the connectors 3 and 4, and the physical information for wiring design. 5,
6, the shape and size of the component pins of the connectors 3 and 4, the nets 11, 12, 13, 14, 15, 21,
It includes information such as 22, 23, 24 and 25. The net information includes the position information of the start point and the end point of the net, and the position information of the start point and the end point of each line segment that divides the net if the net has a shape including a branch or a bend.

The net tracing section 31 detects how signals on the wiring boards 1 and 2 are connected via the connectors 4 and 5. Also, the net tracking unit 31
Identifies the connector for connecting each wiring board, and tracks the location and pin number of the connector parts for connecting the signals of the wiring boards to each other to connect the net of the wiring board 1 and the net of the wiring board 2. The relationship is detected and a net name table between wiring boards as shown in FIG. 3 is output. In the net name table between wiring boards shown in FIG. 3, the nets 21, 12, 13, 14, 15 on the wiring board 1 correspond to the nets 21, 22, 23, 24, 25 on the wiring board 2, respectively. It indicates that

The wiring board crosstalk calculating unit 32 calculates how much noise each net receives from the surrounding nets on each wiring board, and as shown in FIG. 4, for each net for each wiring board. A noise amount table for each net listing the calculation results is output. The wiring board crosstalk calculation unit 32 determines each type of signal flowing through each net and the surrounding nets (for example, TTL, LVTTL, etc.), the clearance between each net and the surrounding nets, and the line length at the clearance. How much noise a net receives from surrounding nets is calculated based on the following formula, for example.

Noise amount = constant C × Σ ((clearance i) × (line length at clearance i)) Here, the constant C is a noise net (nets 16 and 26 in the example of FIG. 1) and a noise net ( In the example of FIG. 1, net 1
1, 21) corresponding to the combination of signal types, and is determined from the observed value as electromagnetically determined, such as the coupling capacitance between wirings.

As for the clearance and the line length, the distance between the center of the wiring and the center of the partner and the line length, which is the distance between them, are obtained for the parallel portion of the noise net and the noise net.
If there are parallel wirings of different distances in the same noise-bearing net and noise net, the distance and the line length are similarly obtained, and the products are added. For simple calculation, it is not necessary to calculate non-parallel portions such as a pattern that bends and gradually separates.

It should be noted that the nets around which the noise amount is calculated are in a range in which it is recognized that the calculated noise amount hardly changes even if the noises of the nets farther away from the noise receiving net are added. It is the net. That is, for example, it is a pattern having a parallel wiring portion having a clearance of several mm or less with respect to the noise net. If the calculation amount may be large, the influence of all nets on the wiring board may be added.

The inter-wiring-board crosstalk calculator 33 calculates the net noise amount table for each net of the wiring boards 1 and 2 and the inter-wiring board net name table as shown in FIG.
The noise amount of the net between the electric component 5 mounted on the wiring board 1 and the electric component 6 mounted on the wiring board 2 is calculated. That is, by referring to the connection relationship between nets on each wiring board from the wiring board net name table, the noise amount of each net noise amount data of each wiring board stored in the net noise amount table is added. , Wiring board 1
The noise amount of the net 11 calculated by the wiring board crosstalk calculating unit 32 for the net 11 and the net 21 between the electric component 5 mounted on the wiring board 6 and the electric component 6 mounted on the wiring board 2. And net 2
Sum the noise amount of 1. Similarly, the total noise amount of the net 12 and the noise amount of the net 22 respectively calculated by the wiring board crosstalk calculating unit 32, the total noise amount of the net 13 and the noise amount of the net 23, the noise amount of the net 14 and the net amount. Total noise amount of 24, and net 15
And the noise amount of the net 25 is calculated.

The signal-based noise limit value table 34 is shown in FIG.
As shown in, the allowable range of the noise amount in each net or the maximum allowable noise amount is shown. The content of the signal-based noise limit value table 34 is set based on the limit values input in advance for each signal from the input unit 30. It should be noted that a signal extending over two wiring boards is input to each signal of one wiring board and is set as the maximum allowable noise amount.

The limit value comparison / judgment unit 35 refers to the signal-based noise limit value table 34, and the noise amount on each net obtained by adding the noise amounts of the connected nets falls within the allowable range. Determine whether or not The output unit 36 is
For example, as shown in FIG. 6, the noise amount of each connected net and the noise amount indicating whether the noise amount is within the allowable range or outside the allowable range and the wiring availability report data are displayed or printed and output. .

Next, the crosstalk noise amount verification operation for the example of the connector connection substrate of FIG. 1 by the crosstalk noise amount verification device of FIG. 2 will be described.

First, the input section 30 inputs data of the wiring boards 1 and 2 for verifying the amount of crosstalk noise. Next, the net tracking unit 31 detects the net connection relationship and obtains the inter-wiring-board net name table shown in FIG.

Next, the wiring board crosstalk calculating section 32 calculates how many mV of noise a signal flowing through each net on each wiring board may receive in each of the wiring board 1 and the wiring board 2, and the wiring is calculated. For each board 1 and wiring board 2,
As shown in FIG. 4, a net noise amount table for each number of wiring boards is output.

Next, the inter-wiring-board crosstalk calculation unit 33 refers to the connection relation between the nets on each wiring board from the inter-wiring board net name table, and each wiring board stored in the net noise amount table. For the net consisting of the net 11 and the net 21 between the electric component 5 mounted on the wiring board 1 and the electric component 6 mounted on the wiring board 2, , The noise amount of the net 11 and the noise amount of the net 21 are summed. Similarly, the noise amount of net 12 and net 2
2 noise amount, net 13 noise amount and net 23 noise amount, net 14 noise amount and net 24 noise amount, net 15 noise amount and net 25 noise amount And the sum is calculated.

Then, the limit value comparison / determination unit 35 performs the process shown in FIG.
6 to determine whether the noise amount on each net is within the allowable range, and finally the output unit 36 outputs the noise amount and wiring availability report shown in FIG. Output the data.

Next, FIG. 7 shows another example of the connector connection board which is the target of the crosstalk noise amount verification apparatus of the present invention.

The combination board is composed of three boards: the wiring board 100, the wiring board 200, and the wiring board 300.

The connectors 400 and 401 and the connector 50
Wiring board 100, wiring board 200
And net 101, net 201, net 301, net 102, net 202, and net 3 on the wiring board 300.
02, net 103, net 203, net 303, net 104, net 204, net 304, net 10
5, the net 205, and the net 305 are connected to each other. In addition, the wiring board 300 includes an electric component 600.
However, the electric component 700 is mounted on the wiring board 200. For example, the net 301 is connected to the electric component 600, the net 201 is connected to the electric component 700, and the net 101 is connected to the connectors 400 and 401 and the connectors 500 and 500.
It is connected to the nets 201 and 301 via 501. A net including the net 101, the net 201, and the net 301 serves as an interface signal between the electric components 600 and 700. In the wiring board 100, the net including the net 101, the net 201, and the net 301 receives crosstalk from the net 106 having a wiring portion parallel to the net 101 on the wiring board 100. On the wiring board 200, crosstalk noise is received from the net 206 having a wiring portion parallel to the net 201. In the wiring board 300, the crosstalk noise is received from the net 306 having a wiring portion parallel to the net 301 on the wiring board 300. Receive.

Next, the crosstalk noise amount verification operation for the example of the connector connection substrate of FIG. 7 by the crosstalk noise amount verification device of FIG. 2 will be described.

First, the input section 30 inputs data of the wiring boards 100, 200, 300 for verifying the amount of crosstalk noise. Next, the net tracking unit 31 detects the net connection relationship to obtain the inter-wiring-board net name table shown in FIG.

Next, the wiring board crosstalk calculation section 32 causes the wiring board 100, the wiring board 200, and the wiring board 300.
What is the signal flowing through each net on each wiring board?
It is calculated whether noises of mV may be received, and as shown in FIG. 9, a net noise amount table for each wiring board 100, wiring board 200, and wiring board 300 is output.

Next, the inter-wiring-board crosstalk calculation unit 33 refers to the connection relation between the nets on each wiring board from the inter-wiring board net name table, and each wiring board stored in the net noise amount table. The noise amount of each net noise amount data is added, and the net 101 and the net 201 between the electric component 600 mounted on the wiring board 300 and the electric component 700 mounted on the wiring board 200 are added.
For the net consisting of
Noise amount of 1 and noise amount of net 201 and net 301
And the noise amount of. Similarly, the sum of the noise amount of the net 102, the noise amount of the net 202 and the noise amount of the net 302, the sum of the noise amount of the net 103, the noise amount of the net 203 and the noise amount of the net 303, net 1
04 noise amount and net 204 noise amount and net 30
4 and the noise amount of the net 105, the noise amount of the net 205, and the noise amount of the net 305 are calculated.

Then, the limit value comparison / determination unit 35 performs the process shown in FIG.
Referring to the signal noise limit value table 34 shown in 0,
It is determined whether or not the noise amount on each net is within the allowable range, and the output unit 36 finally outputs the noise amount and the wiring availability report data shown in FIG.

[0035]

As described above, according to the present invention,
Based on the positional information of the nets on the plurality of wiring boards connected to the input connector and the connection relationship of the connectors connecting the wiring boards, the connection relationship between the nets on each wiring board is detected, and each connection on each wiring board is detected. Calculate how much noise a net receives from the surrounding nets, refer to the above connection relation, add the noise amount of each wiring board for the connected net, and add the net consisting of the connected nets. By determining whether the amount of noise on the board is within the allowable range, it is possible to estimate the crosstalk for signals that span multiple boards to a certain degree of accuracy, increase the wiring density, and increase the speed. A wiring board having an interface can be realized.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a connector connection board which is a target of a crosstalk noise amount verification device of the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment of a crosstalk noise amount verification device of the present invention.

FIG. 3 is a diagram showing an example of a net name table between wiring boards according to the present invention.

FIG. 4 is a diagram showing an example of a net noise amount table according to the present invention.

FIG. 5 is a diagram showing an example of a signal-based noise limit value table according to the present invention.

FIG. 6 is a diagram showing an example of noise amount and wiring availability report data according to the present invention.

FIG. 7 is a perspective view showing another example of a connector connection board which is a target of the crosstalk noise amount verification device of the present invention.

FIG. 8 is a diagram showing another example of a net name table between wiring boards according to the present invention.

FIG. 9 is a diagram showing another example of a net noise amount table according to the present invention.

FIG. 10 is a diagram showing another example of a signal-based noise limit value table according to the present invention.

FIG. 11 is a diagram showing another example of noise amount and wiring availability report data according to the present invention.

[Explanation of symbols]

1, 2 Wiring board 3, 4 Connector 5, 6 Electrical component 11, 12, 13, 14, 15, 16 Net 21, 22, 23, 24, 25, 26 Net 30 Input section 31 Net tracing section 32 Wiring board crosstalk Calculation unit 33 Cross-talk between wiring boards Calculation unit 34 Signal-based noise limit value table 35 Limit value comparison / determination unit 36 Output units 100, 200, 300 Wiring boards 400, 401, 500, 501 Connectors 600, 700 Electrical components 101, 102, 103, 104, 105, 106 Nets 201, 202, 203, 204, 205, 206 Nets 301, 302, 303, 304, 305, 306 Nets

Claims (2)

[Claims] 1. A connection relationship between nets on each wiring board is detected based on positional information of nets on a plurality of wiring boards connected to a connector and a connection relationship of connectors connecting the wiring boards, and Calculate how much noise each net receives from the surrounding nets on the wiring board, add the noise quantity of each wiring board for the net to be connected by referring to the above connection relation, and A method for verifying the amount of crosstalk noise, which comprises determining whether or not the amount of noise on a net made up of nets is within an allowable range. 2. An input unit for inputting position information of nets on a plurality of wiring boards to be connected by a connector and a connection relation of a connector connecting the wiring boards, and position information of the nets on the plurality of wiring boards and a wiring board. Calculates how much noise each net receives from the surrounding nets on each wiring board, and the net tracking unit that detects the connection relationship between the nets on each wiring board based on the connection relationship of the connectors that connect With reference to the wiring board crosstalk calculation unit, and the connection relationship between the nets on each wiring board,
A crosstalk calculation unit between wiring boards that adds the noise amount of each wiring board for the connected nets, and a limit that determines whether the noise amount on the nets that are connected is within the allowable range A crosstalk noise amount verification device, comprising: a value comparison determination unit.