Quick positioning method and system for imitated difference after parasitic parameter extraction, and storage medium

Abstract

The invention discloses a quick positioning method and system for imitated differences after parasitic parameter extraction and a storage medium. The method comprises the steps that a script program is started to modify capacitance values and resistance values of a plurality of detailed standard parasitic parameter format DSPF files, the modified files are imported into a simulation program for simulation, and a capacitance simulation comparison result file and a resistance simulation comparison result file are obtained; if the difference of the resistance simulation comparison results is large, modifying the resistance values of a part of subnet lists Net in the resistance simulation result comparison file into minimum values by using a script program, and positioning the Net causing the difference of the simulation results by using a dichotomy algorithm; if the difference of the capacitance simulation comparison results is large, rapidly comparing the difference of the total capacitance in all the Nets with the capacitance difference between different Nets by using a script program; and inputting the netlist file obtained in the previous step into a post-simulation program for simulation to obtain a capacitance difference positioning result between different Nets.

Description

Technical Field

[0001] The present application relates to integrated circuit (IC) electronic design automation (EDA) technology, and in particular to a method, system and storage medium for quickly locating differences after parasitic parameter extraction. Background Art

[0002] Metal interconnects with a width of only nanometers and distributed in multiple layers are widely present in integrated circuit chips. Their electromagnetic parasitic effects have become a key factor affecting circuit performance and even determining whether the circuit can work normally.

[0003] The typical integrated circuit design process usually includes circuit design, pre-simulation, layout design and post-simulation. Among them, post-simulation (abbreviated as "post-simulation") refers to the simulation after the layout design is completed, combining the parasitic parameters of the circuit and the connection conditions between various circuit units, and analyzing the circuit based on the simulation results to ensure that the circuit meets the design requirements. A process called parasitic extraction is set between layout design and circuit simulation. Parasitic extraction is the basis of modeling, analysis, and simulation in chip physical design. Only through parasitic extraction can the circuit delay be estimated, signal integrity and power integrity analysis be achieved, and then the various performance indicators of the entire circuit design can be verified.

[0004] The main task of parasitic parameter extraction is to calculate the equivalent resistance and capacitance parameters of interconnects and form a circuit netlist. With the development of process technology and the increase in circuit scale, how to accurately and quickly extract parasitic parameters, especially the extraction of capacitance parameters, and then accurately simulate or analyze the reliability of circuits with parasitic parameters, has become increasingly important for ensuring design quality, improving manufacturing yield, reducing costs and shortening design cycles.

[0005] As the industry places higher and higher demands on the calculation accuracy of parasitic parameter extraction, different tools and different methods of the same tool, for example, the netlists extracted by the 2.5D method and the 3D method are definitely different, and the difference between the two will further lead to differences in circuit simulation. However, there is currently a lack of relevant technical solutions for how to quickly analyze whether the circuit design differences in the simulation results come from resistors or capacitors, and which module the resistors or capacitors come from. Summary of the invention

[0006] In view of this, the main purpose of the present invention is to provide a method, system and storage medium for quickly locating simulation differences after parasitic parameter extraction, so as to quickly locate the source of simulation result differences in parasitic parameter netlists extracted by different parasitic parameter extraction tools, or in parasitic parameter netlists extracted by the same extraction tool but using different methods.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for quickly locating differences after parasitic parameter extraction includes the following steps:

[0009] Start the script program to modify the capacitance values ​​and resistance values ​​of multiple detailed standard parasitic parameter format DSPF files respectively, and import the modified files into the simulation program for simulation, and obtain capacitance simulation comparison result files and resistance simulation comparison result files respectively;

[0010] If the resistance simulation comparison results are greatly different, use a script program to modify the resistance values ​​of some subnet tables Net in the resistance simulation result comparison file to minimum values, and use a binary algorithm to locate the Net that causes the difference in simulation results;

[0011] If the capacitance simulation comparison results are greatly different, a script program is used to quickly compare the difference in total capacitance in all Nets and the capacitance difference between different Nets; and the script program is automatically sorted by capacitance value;

[0012] The netlist file obtained in the above steps is input into the simulation program for simulation, and the capacitance difference positioning results between different Nets are obtained by horizontal and vertical comparison analysis of the simulation results.

[0013] Wherein: after the step of using the script program to quickly compare the difference in total capacitance of all Nets and the difference in capacitance between different Nets, the method further includes:

[0014] A plurality of capacitance adjustment files are automatically outputted through a program script, which are obtained by adjusting capacitance values ​​with large capacitance differences between some subnet tables Net and Net using the modified capacitance standard reference file as a standard.

[0015] The "if the difference in the resistance simulation comparison results is large" means that the difference in the simulation results of the resistance values ​​is greater than 0.5%.

[0016] The use of a script program to modify the resistance value of some subnet tables Net in the resistance simulation result comparison file to a minimum value means that the resistance value is not greater than 1E-10Ω.

[0017] In one embodiment, if the capacitance simulation comparison result difference is large, it means that the capacitance simulation result difference is greater than 0.3%.

[0018] In another embodiment, if the capacitance simulation comparison results have a large difference, it means that the capacitance simulation results have a difference greater than 0.01%.

[0019] A rapid location system for parasitic parameter extraction and post-simulation difference, comprising:

[0020] A capacitance value / resistance value modification module is used to start a script program to modify capacitance values ​​and resistance values ​​of multiple detailed standard parasitic parameter format (DSPF) files respectively, and import the modified files into a simulation program for simulation, and obtain capacitance simulation comparison result files and resistance simulation comparison result files respectively;

[0021] A resistance simulation result difference comparison module, if the resistance simulation comparison result is greatly different, a script program is used to modify the resistance value of some Nets in the resistance simulation result comparison file to a minimum value, and a binary algorithm is used to locate the Net that causes the simulation result difference;

[0022] A capacitance simulation result difference comparison module, if the capacitance simulation comparison result difference is large, uses a script program to quickly compare the difference in total capacitance in all Nets and the difference in CC capacitance between Nets; and enables the script program to automatically sort by capacitance value;

[0023] The post-simulation result output module is used to input the netlist file obtained above into the post-simulation program for simulation, and to compare and analyze the simulation results horizontally and vertically to obtain the positioning results of which capacitance differences between Nets are most likely to cause simulation differences.

[0024] Wherein: the capacitance simulation result difference comparison module is also used to automatically output multiple capacitance value adjustment files obtained by adjusting the capacitance values ​​with large capacitance differences between some subnet tables Net and Net based on the modified capacitance standard reference file through a program script.

[0025] A storage medium stores a computer program or instruction; the computer program is configured to implement the method for quickly locating the difference after parasitic parameter extraction when executed by at least one processor; the storage medium is a computer-readable storage medium.

[0026] Compared with the prior art, the method, system and storage medium for quickly locating the difference after parasitic parameter extraction of the present invention have the following beneficial effects:

[0027] The application of the rapid positioning method, system and storage medium of the present invention can improve the positioning speed of the difference in the simulation results after the netlist (Netlist) in the integrated circuit (IC) electronic design automation (EDA) process, which is conducive to the rapid positioning of the parasitic parameter extraction module to the key core subnetlist (Net) module, thereby facilitating the rapid repair of problems / defects in the parasitic parameter extraction tool and the rapid positioning of the circuit module with problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A flow chart of a method for quickly locating differences after parasitic parameter extraction according to an embodiment of the present invention;

[0029] Figure 2 This is a functional block diagram of a system for quickly locating differences after parasitic parameter extraction according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0031] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0032] The core idea of ​​the present invention is to provide a set of rapid positioning methods for post-simulation differences of parasitic parameter extraction that have been repeatedly tested and verified and are practical, and a program script system including corresponding algorithm modules, so as to quickly locate the source of the difference in the post-simulation results. Since the netlist (Netlist) extracted by the parasitic parameters contains both resistors (R) and capacitors (C). In the initial state, the program script system can be used to change the resistance and capacitance of the first netlist A and the second netlist B to minimum values, respectively, and compare the difference of the C-only netlist (Netlist) or the R-only netlist (Netlist) respectively, to quickly locate whether the resistor "R" has a problem or the capacitor "C" has a problem. Then use the script system to locate the circuit module with problems.

[0033] Figure 1 The flowchart of the method for quickly locating the difference after parasitic parameter extraction according to the embodiment of the present invention is shown.

[0034] Assume that there are two parasitic parameter netlist files stored in a standard format, such as Detailed Standard Parasitic Format (DSPF) files, namely file A.dspf and file B.dspf, wherein file A.dspf is a reference file and file B.dspf is a comparison file.

[0035] The present invention takes the implementation process of the following embodiment as an example to illustrate the need to quickly locate which difference resistances or difference capacitances in file B and which differences exist in file A that lead to inconsistency between the simulation result data of file B and the simulation result data of file A.

[0036] like Figure 1 As shown in FIG. 1 , the method for quickly locating the difference after parasitic parameter extraction mainly includes the following steps:

[0037] Step 11: Use a script program to modify the capacitance and resistance values ​​of file A and file B respectively, and obtain four files, A_C-only, A_R-only, B_C-only, and B_R-only; then import the four files into a simulation program for simulation analysis, and compare the simulation results of A_C-only and B_C-only with the simulation results of A_R-only and B_R-only.

[0038] Step 12: If the simulation results of A_R-only and B_R-only are very different, continue to use the script program; change the resistance of some Nets in A_R-only and B_R-only files to the minimum value of 1E-10Ω (ohm). Use the binary algorithm to quickly locate which subnet table (Net) or which subnet tables (Net) have different resistances that cause the difference in simulation results.

[0039] Here, the Net is part of the Netlist, and its location depends on the difference between the parasitic parameters of the Net in question, resistance, and capacitance, and the parasitic parameters of the comparison Net. The binary search algorithm draws on the design idea of ​​the binary search algorithm, and evenly groups the number of Nets to be located, changes them to minimum values, and then runs the simulation program. For example, assuming there are 10 Nets in total, they can be divided into two groups, that is, the same 5 Nets in Group A and Group B are all changed to minimum values, and the simulation program is run to find the difference between the two. If the difference is not big, for example, the difference of the simulation results of the resistance value does not exceed 0.5% (preferably, not more than 0.1%); the difference of the simulation results of the capacitance value does not exceed 0.3% (preferably, not more than 0.01%), it indicates that the remaining unchanged Net is not the key Net, and the modified Net needs to be further checked; if the simulation results are very different, for example, the difference of the simulation results of the resistance value is greater than 0.5% (preferably, the difference is greater than 0.1%); the difference of the simulation results of the capacitance value is greater than 0.3% (preferably, the difference is greater than 0.01%), it means that the key Net may still be in the unchanged Netlist, and then it is necessary to continue to iterate. The recursion is continued until the difference in the simulation results is approximately zero, that is, when the difference in the simulation results is within the given error range, the iteration is terminated. Finally, the parasitic parameter extraction tool can also be used to manually check and locate the key Net.

[0040] In this embodiment, resistors are used as an example for explanation. The capacitance values ​​in file A and file B are changed to extremely small values, such as 1E-30fF (femto Farad), and the netlist of R_only is obtained, in which there are 10 Nets in each. We can keep only the resistance value of one Net unchanged, and change the resistance values ​​of the other nine Nets to extremely small values ​​(such as not more than 1E-10Ω), and then compare the simulation results. If the resistance of one Net IN remains unchanged, the difference between it and the simulation results of the nine Nets with extremely small resistance values ​​is large (for example, the resistance value difference is greater than 0.3%), which means that there is a large difference in the Net IN. At this time, we can check whether the parasitic parameter extraction tool has defects in the processing of the Net IN.

[0041] When there are a large number of resistors in the file, such as more than several million resistors, it is obviously impractical to test them one by one. At this time, you can also learn from the binary algorithm of the program, batch modify the resistance value of the Net and then quickly locate it, which can greatly improve the search and positioning efficiency.

[0042] Step 13: If the simulation results of A_Conly and B_Conly are greatly different, use the script program to quickly compare the difference in the total capacitance of all Nets and the difference in CC capacitance between Nets, and let the script program automatically sort by capacitance value; at this time, the program script will also automatically output multiple B_Conly_adjust* files, which are mainly adjusted by the capacitance value of some Nets with large CC capacitance differences with the capacitance standard reference file A_Conly.

[0043] In this embodiment, capacitors are used as an example. The resistors in file A and file B are changed to extremely small values ​​(such as 1E-10Ω) to obtain a C-only netlist. For example, a program script can be used to quickly find which Nets and Nets have CC capacitance values ​​greater than 4fF and the absolute value of the error is greater than 8%.

[0044] At this time, it is necessary to select such Net pairs. Assuming there are 100 pairs in total, you can use the script program to divide them into 5 parts. In each part, the capacitance values ​​of the selected 20 pairs of Nets are changed to files that are approximately the same as the capacitance values ​​in the standard file using the script program. Finally, perform simulation tests to compare which simulation results are closest to those of the standard file. This means that the capacitance of the 20 pairs of Nets modified by the file is the most critical path for the post-simulation difference. Later, you can use the recursive algorithm to perform binary search on these 20 Nets in turn to further narrow the search range. The above process also uses the design idea of ​​the binary search algorithm. To avoid repetition, the detailed process will not be repeated here.

[0045] Step 14: Finally, the netlist file obtained above is input into the post-simulation program for simulation, and the simulation results are compared and analyzed horizontally and vertically to determine which CC capacitance differences between Nets are most likely to cause simulation differences, that is, to obtain the capacitance difference positioning results between different Nets.

[0046] The algorithms of the above steps 11 to 13 are all written into the script program and can be automatically run and implemented.

[0047] Figure 2 This is a functional block diagram of a system for quickly locating differences after parasitic parameter extraction according to an embodiment of the present invention.

[0048] like Figure 2 As shown in the figure, the rapid positioning system of the difference after parasitic parameter extraction mainly includes:

[0049] The capacitance value / resistance value modification module is used to start the script program to modify the capacitance value and resistance value of multiple detailed standard parasitic parameter format (Detailed Standard Parasitic Format, DSPF) files respectively, and import the modified files into the simulation program for simulation, and obtain the capacitance simulation comparison result and the resistance simulation comparison result files respectively.

[0050] The resistance simulation result difference comparison module uses a script program to modify the resistance value of some Nets in the resistance simulation result comparison file to a minimum value if the resistance simulation comparison result is greatly different, and uses a binary algorithm to locate the Net position that causes the simulation result difference.

[0051] The capacitance simulation result difference comparison module, if the capacitance simulation comparison result is very different, uses a script program to quickly compare the difference in total capacitance in all Nets and the difference in CC capacitance between any Net and the rest of the Nets; and the script program is automatically sorted by capacitance value. It is also used to automatically output multiple B_Conly_adjust* files through the program script. The B_Conly_adjust* files are mainly obtained by adjusting the capacitance values ​​with large CC capacitance differences between some Nets and the rest of the Nets based on A_Conly as the standard.

[0052] The post-simulation result output module is used to input the netlist file obtained above into the post-simulation program for simulation, and to obtain the capacitance difference positioning result between different Nets by horizontal and vertical comparison analysis of the simulation results.

[0053] Based on the same inventive concept, the present invention also provides a device including the rapid positioning system of the parasitic parameter extraction and simulated difference, that is, a rapid positioning device of the parasitic parameter extraction and simulated difference, wherein the rapid positioning system includes the above-mentioned program module, and also includes a memory and at least one processor, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the processor executes the steps of the rapid positioning method of the parasitic parameter extraction and simulated difference described in the above-mentioned embodiments.

[0054] The present invention also provides a storage medium, preferably a readable storage medium, which stores a computer program or instruction. The computer program is configured to implement the above-mentioned method for quickly locating differences after parasitic parameter extraction when executed by at least one processor.

[0055] The readable storage medium is a computer-readable storage medium, which may be a non-volatile computer-readable storage medium or a volatile computer-readable storage medium. Specifically, the readable storage medium may be a tangible device capable of maintaining and storing instructions used by an instruction execution device, such as an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination of the above. The readable storage medium more specifically includes: a computer hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash chip, a static random access memory (SRAM), a CD-ROM, a DVD, etc.

[0056] The application of the rapid positioning method and system of the present invention can not only solve the problem of rapid positioning of parasitic parameter netlists extracted by different parasitic parameter extraction tools, but also solve the problem of rapid positioning of simulation differences caused by parasitic parameter netlists extracted by the same tool but with different methods.

[0057] The above description is only a description of the preferred embodiments of the present application in combination with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A method for quickly locating differences after parasitic parameter extraction, characterized in that: The steps include: Start the script program to modify the capacitance values ​​and resistance values ​​of multiple detailed standard parasitic parameter format DSPF files respectively, and import the modified files into the simulation program for simulation, so as to obtain capacitance simulation comparison result files and resistance simulation comparison result files respectively; If the resistance simulation comparison results are greatly different, use a script program to modify the resistance values ​​of some subnet tables Net in the resistance simulation result comparison file to minimum values, and use a binary algorithm to locate the Net that causes the difference in simulation results; If the capacitance simulation comparison results are greatly different, a script program is used to quickly compare the total capacitance difference in all Nets and the capacitance difference between any Net and the rest of the Nets; and the script program is automatically sorted by capacitance value; The netlist file obtained in the above steps is input into the simulation program for simulation, and the capacitance difference positioning results between different Nets are obtained by horizontal and vertical comparison analysis of the simulation results.

2. The method for quickly locating differences after parasitic parameter extraction according to claim 1 is characterized in that: After the step of using the script program to quickly compare the total capacitance difference in all Nets and the capacitance difference between any Net and the remaining Nets, the following steps are also included: A plurality of capacitance value adjustment files are automatically outputted through a program script after the capacitance values ​​having large capacitance differences between some subnet tables Net and other Nets are adjusted using the modified capacitance standard reference file as a standard.

3. The method for quickly locating differences after parasitic parameter extraction according to claim 1 is characterized in that: The "if the difference in the resistance simulation comparison results is large" means that the difference in the simulation results of the resistance values ​​is greater than 0.5%.

4. The method for quickly locating differences after parasitic parameter extraction according to claim 1 is characterized in that: The use of a script program to modify the resistance value of some subnet tables Net in the resistance simulation result comparison file to a minimum value means that the resistance value is not greater than 1E-10Ω.

5. The method for quickly locating differences after parasitic parameter extraction according to claim 1 or 2, characterized in that: If the capacitance simulation comparison results have a large difference, it means that the capacitance simulation results have a difference greater than 0.3%.

6. The method for quickly locating differences after parasitic parameter extraction according to claim 1 or 2, characterized in that: If the capacitance simulation comparison results have a large difference, it means that the capacitance simulation results have a difference greater than 0.01%.

7. A rapid positioning system for parasitic parameter extraction and post-simulation difference, characterized in that: include: A capacitance value / resistance value modification module is used to start a script program to modify the capacitance values ​​and resistance values ​​of multiple detailed standard parasitic parameter format DSPF files respectively, and import the modified files into a simulation program for simulation, and obtain capacitance simulation comparison result files and resistance simulation comparison result files respectively; A resistance simulation result difference comparison module, if the resistance simulation comparison result is greatly different, a script program is used to modify the resistance value of some Nets in the resistance simulation result comparison file to a minimum value, and a binary algorithm is used to locate the Net position that causes the simulation result difference; A capacitance simulation result difference comparison module, if the capacitance simulation comparison result difference is large, uses a script program to quickly compare the total capacitance difference in all Nets and the CC capacitance difference between any Net and the rest of the Nets; and enables the script program to automatically sort by capacitance value; The post-simulation result output module is used to input the netlist file obtained above into the post-simulation program for simulation, and to compare and analyze the simulation results horizontally and vertically to obtain the positioning results of which capacitance differences between Nets are most likely to cause simulation differences.

8. The rapid positioning system of parasitic parameter extraction and post-simulation difference according to claim 7 is characterized in that: The capacitance simulation result difference comparison module is also used to automatically output multiple capacitance value adjustment files obtained by adjusting the capacitance values ​​with large capacitance differences between some subnet tables Net and other Nets based on the modified capacitance standard reference file through a program script.

9. A storage medium, characterized in that: It stores a computer program or instruction; the computer program is configured to be able to implement the method for quickly locating the difference after parasitic parameter extraction according to claims 1 to 6 when executed by at least one processor; the storage medium is a computer-readable storage medium.

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