JP2005038150A - Transmission line analysis system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To analyze timing and noise simultaneously throughout an electric circuit comprising a plurality of electronic parts and including a clock signal, a control signal and a multi-connection bus signal. <P>SOLUTION: An analytic model generation part 11 creates analytic models of target transmission lines. A timing correction part 12 corrects the timing of bus signals by adding pre-extracted electrical characteristics of transmission lines accumulated in an accumulation part 17 and electrical characteristics of electronic parts accumulated in an accumulation part 15 which are internal delays in the electronic parts depending on control signals. Transmission line analysis software 13 is used on the corrected models to produce a transmission line analysis result 16, which provides a simultaneous analysis of timing and noise in the multi-connection bus signals. A transmission characteristic extraction part 14 then extracts the electrical characteristics of the transmission lines to enable a transmission line analysis of another electric circuit. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to transmission line analysis in electrical circuit design and printed circuit board design, and more particularly to a transmission line analysis system that simultaneously analyzes the timing and noise of an entire electrical circuit and printed circuit board including clock signals, control signals, and bus signals. is there.

  In recent years, the density and speed of printed circuit boards of electrical devices have been increased, and transmission line analysis has been carried out in electrical circuit design and printed circuit board design so that the functions of the printed circuit board can be accurately realized. In transmission line analysis, in order to select electronic parts that realize clock signals without noise and to design transmission lines, it is also necessary to select and transmit electronic parts that propagate bus signals at the same timing among multiple electronic parts. It is implemented from the viewpoint of designing the track.

  Conventionally, as a method for analyzing these two viewpoints simultaneously, for example, by comparing the wiring delay calculated based on the actually wired wiring length with the wiring allowable delay, the arrangement of the electronic components in consideration of the timing and the electronic components are considered. A wiring for connecting the two is designed (for example, see Patent Document 1).

FIG. 6 shows an outline of an electric circuit handled by a conventional analysis system. In FIG. 6, a transmission line 66 that propagates a bus signal connects one driver electronic component 62 and one receiver electronic component 63. A clock signal for controlling the timing of the bus signal is propagated from the electronic component 61 through the transmission line 64 and the transmission line 65. In this electric circuit, the electrical characteristics of the transmission line 64 and the transmission line 65 are used for the transmission line analysis of the transmission line 66, whereby the timing and noise of the bus signal and the clock signal can be analyzed simultaneously.
Japanese Patent Laid-Open No. 11-288431 (page 9, paragraph numbers 0067 and 0068, FIG. 14)

  However, in the conventional electric circuit, the electrical characteristics of the transmission line are limited to the clock signal to the two electronic components of the driver and the receiver, and other than that, a buffer for temporarily storing data is used. It is not possible to analyze an electrical circuit including electronic components and control signals.

  It is an object of the present invention to provide a transmission line analysis system that can simultaneously analyze timing and noise for an entire electric circuit including a clock signal, a control signal, and a multi-connection bus signal composed of a plurality of electronic components. To do.

  In order to solve this problem, the transmission line analysis system of the present invention includes means for generating a transmission line analysis model of an electrical circuit to be analyzed, means for storing electrical characteristics of electronic components, and electrical characteristics of the transmission line. The means for accumulating, the means for correcting the transmission line timing with respect to the analysis model of the transmission line from the electrical characteristics of the stored electronic components and the electrical characteristics of the transmission line, and the transmission line analysis from the analysis model corrected for the timing The transmission line analysis system of the present invention is characterized by comprising means for performing transmission line analysis using software and means for extracting the electrical characteristics of the transmission line from the result of the transmission line analysis. The electrical characteristics of electronic components are the timing at which bus signals are output, and the electrical characteristics of transmission lines are control signals that propagate through the transmission lines. From the electrical characteristics of the transmission line, with respect to the analysis model of the transmission line, it is characterized in that to correct the timing of the bus signals propagating through the transmission line.

  According to the present invention, the transmission line analysis is performed by correcting the timing of the bus signal with respect to the analysis model using the accumulated electrical characteristics of the electronic components and the accumulated electrical characteristics of the transmission line. The timing and noise of the entire electric circuit including a clock signal, a control signal, and a multi-connection bus signal composed of a plurality of electronic components can be analyzed simultaneously.

  According to the present invention, using the electrical characteristics accumulated in the electrical property accumulation unit of the electronic component and the electrical characteristics accumulated in the electrical property accumulation unit of the transmission line, the transmission line is corrected by correcting the timing with respect to the analysis model. By analyzing, it is possible to simultaneously analyze timing and noise for the entire electric circuit including a clock signal, a control signal, and a multi-connection bus signal composed of a plurality of electronic components.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
(Embodiment 1)
FIG. 1 is a configuration block diagram of a timing transmission line analysis system of the present invention. In the figure, 11 is a transmission line analysis model generation unit, 12 is an analysis model timing correction unit, 13 is a transmission line analysis software, 14 is a transmission line electrical characteristic extraction unit, and 15 is an electronic component electrical characteristic storage unit. , 16 is a result of the transmission line analysis, and 17 is an electrical characteristic storage unit of the transmission line.

  FIG. 2 shows an example of an electric circuit handled by the timing transmission line analysis system of the present invention. 21 is an electronic component of the driver of the clock signal and control signal, 22 is an electronic component of the driver of the bus signal, 23 is an electronic component of the receiver of the bus signal, 24 and 25 are electronic components of the buffer of the bus signal, and 26 and 27 are clocks Transmission lines that propagate signals, transmission lines 28 and 29 that propagate bus signals, and transmission lines 210 and 211 that propagate control signals.

  The operation of the electric circuit is as follows. A bus signal is propagated from the electronic component 22 to the electronic component 24 through the transmission line 28. On the other hand, a bus signal is propagated from the electronic component 22 to the electronic component 25 through the transmission line 29. On the other hand, a clock signal for outputting those bus signals from the electronic component 21 is propagated through the transmission line 26. Thereafter, a control signal at a timing of outputting a bus signal to the electronic component 24 is propagated from the electronic component 21 through the transmission line 210, and a control signal of the bus signal is propagated from the electronic component 21 to the electronic component 25 through the transmission line 211. . A bus signal is propagated from the electronic component 24 to the electronic component 23 through the transmission line 28 and the bus signal is propagated from the electronic component 25 to the electronic component 23 through the transmission line 29 according to the control signal propagated to each. Thereafter, in accordance with the clock signal propagated from the electronic component 21 through the transmission line 27, each propagated bus signal is taken into the electronic component 23.

  Next, transmission line analysis will be described with reference to FIG. 31 is an input waveform of the transmission line, 32 is an output waveform of the transmission line, 33 is a threshold value of 0/1 of the electronic components of the receiver, and 34 is an electrical characteristic of the transmission line. The feature of the present invention is that the electrical characteristic 34 of the transmission line is used for correcting the timing of the bus signal in order to simultaneously analyze the timing and noise of the bus signal of multiple connections.

  1 will be described in detail by taking the electric circuit of FIG. 2 as an example. The object of the present invention is to simultaneously analyze the timing and noise of the entire electric circuit illustrated in FIG. In the electric circuit shown in FIG. 2, since the control signals propagated from the transmission lines 210 and 211 are different, the timing at which the electronic component 24 and the electronic component 25 output the bus signal is different. Therefore, by performing transmission line analysis on the transmission line 210 and the transmission line 211 in advance, the electrical characteristics of each transmission line are extracted by the transmission characteristic extraction unit 14 and stored in the storage unit 17. Next, the analysis model generation unit 11 creates each analysis model for the transmission line 28 and the transmission line 29, and the electrical characteristics of the transmission line 210 and the transmission line 211 stored in the electrical characteristic storage unit 17 in advance. Depending on the characteristics and the control signal stored in the electrical property storage unit 15 of the electronic component, the electrical characteristics of the electronic component 24 and the electronic component 25 that are internal delays of the electronic component are added, and the timing correction unit 12 The timing of the bus signal propagating through the transmission line 28 and the transmission line 29 is corrected. On the other hand, the transmission line analysis result 16 is obtained by using the transmission line analysis software 13. As a result, the timing and noise of the bus signal with multiple connections can be analyzed simultaneously.

  Furthermore, by extracting the electrical characteristics of the transmission line 28 and the transmission line 29 from the analysis result 16 in the transmission characteristic extraction unit 14, it becomes possible to analyze the transmission line of other electrical circuits. In addition, since the electrical characteristics of the transmission line are stored in the storage unit 17, even if the transmission line 26, the transmission line 27, the transmission line 210, and the transmission line 211 are electric circuits composed of a plurality of parts, The same analysis can be performed by adding the characteristics.

  Next, the function of the timing correction unit 12 will be described with reference to FIGS. Since the bus signal is normally supplied from a single electronic component, the bus signal 41 and the bus signal 42 in FIG. However, in the present invention, in order to handle a plurality of electronic components and multi-connection bus signals, as shown in FIG. 5, the timing correction amount 53 is used to correct the timing, and the bus signal 41 is changed to the bus signal 51. Using the timing correction amount 54, the timing is corrected and the bus signal 42 is changed to the bus signal 52. As a result, the crosstalk between the bus signals can be analyzed in the same manner as the actual operation. The timing correction amount 53 and the timing correction amount 54 are extracted as electrical characteristics of the transmission line of the clock signal and control signal for the electronic components of the driver and the buffer. In FIG. 1 and FIG. 2, the electrical characteristics of the transmission line 210 and the transmission line 211 stored in the electrical characteristic storage unit 17 are the timing correction amount 53 and the timing correction amount 54.

1 is a configuration block diagram showing Embodiment 1 of the present invention. It is an example of the electric circuit handled by this invention. It is an example of the transmission line analysis handled by this invention. This is a bus signal handled in the present invention. FIG. 5 is a corrected bus signal in which the present invention is applied to FIG. It is an example of the electric circuit handled with the conventional analysis system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Analysis model production | generation part 12 Timing correction | amendment part 13 Transmission line analysis software 14 Transmission characteristic extraction part 15 Electrical characteristic storage part 16 Electronic line result of transmission line analysis 17 Transmission line electrical characteristic storage part 21 Electronic parts (clock signal and control signal) Driver)
22 Electronic components (bus signal driver)
23 Electronic components (bus signal receiver)
24 Electronic components (buffer for bus signals)
25 Electronic components (bus signal buffer)
26 Transmission line (clock signal propagation)
27 Transmission line (Clock signal propagation)
28 Transmission line (Bus signal propagation)
29 Transmission line (Bus signal propagation)
210 Transmission line (propagation of control signal)
211 Transmission line (propagation of control signal)
31 Transmission Line Input Waveform 32 Transmission Line Output Waveform 33 Electronic Component 0/1 Threshold 34 Transmission Line Electrical Characteristics 41 Bus Signal 42 Bus Signal 51 Bus Signal After Timing Correction 52 Bus Signal After Timing Correction 53 Bus Signal Timing correction amount 54 Bus signal timing correction amount 61 Electronic component (clock signal driver)
62 Electronic components (bus signal driver)
63 Electronic components (bus signal receiver)
64 Transmission line (Propagation of clock signal)
65 Transmission line (clock signal propagation)
66 Transmission line (Bus signal propagation)

Claims (2)

  Means for generating a transmission line analysis model of the electric circuit to be analyzed, means for storing the electrical characteristics of the electronic component, means for storing the electrical characteristics of the transmission line, the electrical characteristics of the stored electronic component and the transmission line From the electrical characteristics, means to correct the transmission line timing with respect to the transmission line analysis model, means to analyze the transmission line using the transmission line analysis software from the timing corrected analysis model, and the result of the transmission line analysis A transmission line analysis system comprising means for extracting electrical characteristics of the transmission line.   The electrical characteristic of the electronic component is the timing of outputting the bus signal, the electrical characteristic of the transmission line is a control signal propagating through the transmission line, and from the accumulated electrical characteristic of the electronic component and the electrical characteristic of the transmission line, The transmission line analysis system according to claim 1, wherein the timing of the bus signal propagating through the transmission line is corrected with respect to the analysis model of the transmission line.