阅读说明：本技术 集成电路频率响应频率点提取与响应曲线计算方法及装置 (Method and device for extracting frequency response frequency points and calculating response curve of integrated circuit ) 是由 唐章宏 邹军 王芬 汲亚飞 黄承清 于 2020-06-24 设计创作，主要内容包括：本申请实施例公开了集成电路频率响应频率点提取与响应曲线计算方法及装置。该方法包括根据超大规模集成电路频域仿真的频率响应的计算需求,在预设频段范围内计算集成电路的谐振频率点及其频率响应,基于谐振频率点将预设频段划分为多个子频段,根据每个子频段的切比雪夫多项式零点获取非均匀频率点,进而计算该非均匀频率点的频率响应,通过插值获得预设频段范围内集成电路的频率响应曲线。本申请可实现提取出满足计算精度要求的数量较少的非均匀频率点,且快速计算出集成电路频域仿真在预设频段内满足精度要求的频率响应曲线,避免难以检测出设计的超大规模集成电路的潜在性能问题。(The embodiment of the application discloses a method and a device for extracting frequency response frequency points and calculating a response curve of an integrated circuit. The method comprises the steps of calculating a resonant frequency point and frequency response of the integrated circuit within a preset frequency band range according to the calculation requirement of frequency response of frequency domain simulation of the ultra-large scale integrated circuit, dividing the preset frequency band into a plurality of sub-frequency bands based on the resonant frequency point, obtaining non-uniform frequency points according to Chebyshev polynomial zero points of each sub-frequency band, further calculating the frequency response of the non-uniform frequency points, and obtaining a frequency response curve of the integrated circuit within the preset frequency band range through interpolation. According to the method and the device, the non-uniform frequency points with small quantity meeting the calculation precision requirement can be extracted, the frequency response curve of the integrated circuit frequency domain simulation meeting the precision requirement in the preset frequency band is rapidly calculated, and the potential performance problem of the designed ultra-large scale integrated circuit is avoided being difficult to detect.)

1. The method for extracting frequency response points and calculating a response curve of an integrated circuit is characterized by comprising the following steps of:

step 100, calculating a resonant frequency point and a frequency response of the very large scale integrated circuit within a preset frequency range by adopting a resonance calculation mode according to a calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and calculating the frequency responses of an initial frequency point and a termination frequency point within the preset frequency range;

step 200, dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end frequency point of each sub-frequency band;

step 300, determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the calculation precision of the frequency domain simulation of the super-large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band;

step 400, taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point, and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel;

step 500, based on the non-uniform frequency points and the frequency response thereof of each sub-band, interpolating at the zero point of the m + 1-time Chebyshev polynomial by an interpolation method to form a frequency response curve of the very large scale integrated circuit at each sub-band;

and step 600, combining the frequency response curves of all the sub-frequency bands to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range.

2. The method as claimed in claim 1, wherein in the step 200, the preset frequency band is divided into n +1 sub-frequency bands according to the calculated n resonant frequency points, together with the start frequency point and the end frequency pointWherein, the starting frequency point, the n resonant frequency points and the ending frequency point sequentially form an endpoint frequency point of each sub-frequency band, including: the n resonance frequency points are connected with the starting frequency point f_lowAnd a termination frequency point f_highIn descending order, denoted as f_low<f₁<…<f_n<f_highDividing the preset frequency band into n +1 sub-frequency bands; wherein, the ith sub-band is:

3. the method according to claim 2, wherein said step 300 determines the number m +1 of scanning frequency points extracted from each sub-band according to the calculation accuracy of the frequency domain simulation of the vlsi circuit and the frequency response of the end point frequency point of each sub-band, wherein said m +1 satisfies the following equation:

in the formula, R_m(f) For the accuracy of the calculation, F (f) is the true value of the frequency response of the integrated circuit at the frequency f,is the maximum value of F (f), L_m(f) For the calculated value of the frequency response curve at the frequency f, the maximum value of F (f) in the sub-band is the maximum value of the frequency response of the frequency points at the left and right end points of the sub-band, i.e. the maximum value

4. The method according to claim 3, wherein in the step 300, the frequency point corresponding to the zero point of the m +1 st-order chebyshev polynomial is set as the scanning frequency point of each sub-band, and the formula of the position of the zero point is:

in the formula (f)_kIn order to be the zero point,

corresponding to each sub-frequency band, the value range of the zero point is f_i-1＜f＜f_iThen, the position formula of the scanning frequency point is:

in the formula (f)_kIs the scanning frequency point.

5. The method of any of claims 1-4, wherein in step 500, the interpolation method includes, but is not limited to: lagrange interpolation, barycentric lagrange interpolation, chebyshev polynomial interpolation, and newton interpolation.

6. The method of claim 5, wherein calculating the resonant frequency point and the frequency response of the VLSI within the predetermined frequency band using the resonance calculation mode comprises: and writing a generalized eigenvalue equation of the continuity equation of the ultra-large scale integrated circuit field through a region discretization column by adopting a resonance calculation mode, solving the generalized eigenvalue equation to obtain a plurality of eigenvalues and eigenvectors, wherein the eigenvalues correspond to resonance frequency points of electromagnetic waves propagated in a dielectric layer of the integrated circuit under the passive condition of the ultra-large scale integrated circuit, the eigenvectors corresponding to each resonance frequency point correspond to the distribution of the field under the resonance frequency points, and the frequency response corresponding to the resonance frequency points is obtained according to the distribution of the field.

7. An integrated circuit frequency response frequency point extraction and response curve calculation device, comprising:

the resonance frequency point calculation module is used for calculating the resonance frequency point and the frequency response of the very large scale integrated circuit within a preset frequency range by adopting a resonance calculation mode according to the calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and calculating the frequency responses of the initial frequency point and the termination frequency point within the preset frequency range;

the first processing module is used for dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end point frequency point of each sub-frequency band;

the second processing module is used for determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the calculation precision of the frequency domain simulation of the super-large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band;

the third processing module is used for taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel;

a fourth processing module, configured to perform interpolation at a zero point of the m + 1-order chebyshev polynomial by using an interpolation method based on the non-uniform frequency point and the frequency response of the frequency sub-band, so as to form a frequency response curve of the very large scale integrated circuit in each frequency sub-band;

and the fifth processing module is used for combining the frequency response curves of all the sub-frequency bands to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range.

8. The apparatus as claimed in claim 7, wherein said first processing module divides said preset frequency band into n +1 sub-bands according to the calculated n resonant frequency points, together with said start frequency point and end frequency point, whereinThe starting frequency point, the n resonant frequency points and the ending frequency point sequentially form an end point frequency point of each sub-frequency band, and the method comprises the following steps: the n resonance frequency points are connected with the starting frequency point f_lowAnd a termination frequency point f_highIn descending order, denoted as f_low<f₁<…<f_n<f_highDividing the preset frequency band into n +1 sub-frequency bands; wherein, the ith sub-band is:

9. the apparatus of claim 8, wherein the second processing module determines the number m +1 of scanning frequency points extracted from each sub-band according to the calculation precision of the frequency domain simulation of the vlsi circuit and the frequency response of the endpoint frequency point of each sub-band, wherein the m +1 satisfies the following equation:

in the formula, R_m(f) For the accuracy of the calculation, F (f) is the true value of the frequency response of the integrated circuit at the frequency f,is the maximum value of F (f), L_m(f) For the calculated value of the frequency response curve at the frequency f, the maximum value of F (f) in the sub-band is the maximum value of the frequency response of the frequency points at the left and right end points of the sub-band, i.e. the maximum value

10. The method according to claim 9, wherein the frequency point corresponding to the zero point of the m +1 st-order chebyshev polynomial in the second processing module is set as the scanning frequency point of each sub-band, and the formula of the position of the zero point is:

in the formula (f)_kIn order to be the zero point,

corresponding to each sub-frequency band, the value range of the zero point is f_i-1＜f＜f_iThen, the position formula of the scanning frequency point is:

in the formula (f)_kIs the scanning frequency point.

Technical Field

The invention relates to the field of integrated circuit frequency domain simulation, in particular to a method and a device for extracting frequency response frequency points and calculating a response curve of an integrated circuit.

Background

Integrated circuits have played a very important role in various industries and are a cornerstone of modern information society. It is a miniature electronic device or component, and is made up by adopting a certain technological process to make the elements of transistor, resistor, capacitor and inductor, etc. required in a circuit and wiring interconnection together, and make them be made into a small piece or several small pieces of semiconductor wafer or medium substrate, then package them in a tube shell so as to obtain the miniature structure with required circuit function. The inter-Chip interconnections between the unit circuits of the integrated circuit, the PCB and the Microwave Multi-Chip Module (MMCM) cause considerable parasitic effects. Meanwhile, no matter the chip or the component, the package part for protecting the circuit and supporting the whole circuit structure is unavoidable, and some package structures such as a feeder wire or a plate, a ground wire or a plate, a chip lead-out wire or a strip, a via hole between multiple layers of metal plates, and the like also have obvious influence on the transmission of high-speed signals.

In order to study the influence of the layout structure of the integrated circuit, the via holes between the integrated circuit multilayer metal plates and the like on the signal transmission of the integrated circuit, the frequency domain response of the multiple ports of the integrated circuit within a certain frequency band needs to be studied, such as the curve of a scattering parameter matrix S changing along with frequency, the curve of an impedance matrix Z changing along with frequency, the curve of a transmission matrix T changing along with frequency and the like in a multi-port network preset frequency band, and whether the connection of the layout structure of the integrated circuit, the via holes between the integrated circuit multilayer metal plates and the like has influence on the signal transmission of the integrated circuit is determined according to the frequency domain response characteristics of the ports. The existing frequency domain response curve is calculated by providing scanning frequency points which are uniformly distributed in a preset frequency band within a certain preset frequency band range, calculating frequency response values of the scanning frequency points, and connecting the values into a curve to obtain the frequency response curve to be calculated.

However, in the process of implementing the present invention, the inventor finds that, in the existing integrated circuit frequency domain simulation extraction of uniformly distributed scanning frequency points, the number of scanning frequency points required to meet the specified calculation accuracy is large, the corresponding calculation amount is large, the calculation efficiency is poor, and meanwhile, the effect in capturing details of the frequency domain response is poor, so that the calculated frequency response of the very large scale integrated circuit in the preset frequency band has a large error with the actual frequency response, and it is difficult to detect the potential performance problem of the designed very large scale integrated circuit.

Disclosure of Invention

The embodiment of the application provides a method and a device for extracting frequency response points and calculating response curves of an integrated circuit, which can realize the extraction of a small number of non-uniform frequency points meeting the calculation precision requirement, quickly calculate the frequency response curves of the frequency domain simulation of the integrated circuit meeting the precision requirement in a preset frequency band, and avoid the problem that the potential performance of a designed ultra-large scale integrated circuit is difficult to detect.

In a first aspect, an embodiment of the present application provides a method for extracting frequency points and calculating a response curve of an integrated circuit frequency response, where the method includes:

step 100, calculating a resonant frequency point and a frequency response of the very large scale integrated circuit within a preset frequency range by adopting a resonance calculation mode according to a calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and calculating the frequency responses of an initial frequency point and a termination frequency point within the preset frequency range;

step 200, dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end frequency point of each sub-frequency band;

step 300, determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the calculation precision of the frequency domain simulation of the super-large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band;

step 400, taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point, and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel;

step 500, based on the non-uniform frequency points and the frequency response thereof of each sub-band, interpolating at the zero point of the m + 1-time Chebyshev polynomial by an interpolation method to form a frequency response curve of the very large scale integrated circuit at each sub-band;

and step 600, combining the frequency response curves of all the sub-frequency bands to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range.

As a possible implementation manner, in the step 200, dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonant frequency points, together with the start frequency point and the end frequency point, where the start frequency point, the n resonant frequency points, and the end frequency point sequentially form an end frequency point of each sub-frequency band, and the method includes: the n resonance frequency points are connected with the starting frequency point f_lowAnd a termination frequency point f_highIn descending order, denoted as f_low<f₁<…<f_n<f_highDividing the preset frequency band into n +1 sub-frequency bands; wherein, the ith sub-band is:

as a possible implementation manner, the determining step 300 determines, according to the calculation precision of the frequency domain simulation of the very large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-band, the number m +1 of the scanning frequency points extracted from each sub-band, where m +1 satisfies the following equation:

in the formula, R_m(f) For the accuracy of the calculation, F (f) is the true value of the frequency response of the integrated circuit at the frequency f,is the maximum value of F (f), L_m(f) For the calculated value of the frequency response curve at the frequency f, the maximum value of F (f) in the sub-band is the maximum value of the frequency response of the frequency points at the left and right end points of the sub-band, i.e. the maximum value

As a possible implementation manner, in setting the frequency point corresponding to the zero point of the m +1 st-order chebyshev polynomial in the step 300 as the scanning frequency point of each sub-band, the position formula of the zero point is:

in the formula (f)_kIn order to be the zero point,

corresponding to each sub-frequency band, the value range of the zero point is f_i-1＜f＜f_iThen, the position formula of the scanning frequency point is:

in the formula (f)_kIs the scanning frequency point.

As a possible implementation manner, in the step 500, the interpolation method includes, but is not limited to: lagrange interpolation, barycentric lagrange interpolation, chebyshev polynomial interpolation, and newton interpolation.

As a possible implementation manner, the calculating, by using the resonance calculation mode, a resonance frequency point of the very large scale integrated circuit within a preset frequency band and a frequency response thereof includes: and writing a generalized eigenvalue equation of the continuity equation of the ultra-large scale integrated circuit field through a region discretization column by adopting a resonance calculation mode, solving the generalized eigenvalue equation to obtain a plurality of eigenvalues and eigenvectors, wherein the eigenvalues correspond to resonance frequency points of electromagnetic waves propagated in a dielectric layer of the integrated circuit under the passive condition of the ultra-large scale integrated circuit, the eigenvectors corresponding to each resonance frequency point correspond to the distribution of the field under the resonance frequency points, and the frequency response corresponding to the resonance frequency points is obtained according to the distribution of the field.

In a second aspect, an embodiment of the present application provides an integrated circuit frequency response frequency point extraction and response curve calculation apparatus, including:

the resonance frequency point calculation module is used for calculating the resonance frequency point and the frequency response of the very large scale integrated circuit within a preset frequency range by adopting a resonance calculation mode according to the calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and calculating the frequency responses of the initial frequency point and the termination frequency point within the preset frequency range;

the first processing module is used for dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end point frequency point of each sub-frequency band;

the second processing module is used for determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the calculation precision of the frequency domain simulation of the super-large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band;

the third processing module is used for taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel;

a fourth processing module, configured to perform interpolation at a zero point of the m + 1-order chebyshev polynomial by using an interpolation method based on the non-uniform frequency point and the frequency response of the frequency sub-band, so as to form a frequency response curve of the very large scale integrated circuit in each frequency sub-band;

and the fifth processing module is used for combining the frequency response curves of all the sub-frequency bands to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range.

As a possible implementation manner, in the first processing module, the dividing, according to the calculated n resonant frequency points, the starting frequency point and the ending frequency point, the preset frequency band into n +1 sub-frequency bands, where the starting frequency point, the n resonant frequency points, and the ending frequency point sequentially form an endpoint frequency point of each sub-frequency band, includes: the n resonance frequency points are connected with the starting frequency point f_lowAnd a termination frequency point f_highIn descending order, denoted as f_low<f₁<…<f_n<f_highDividing the preset frequency band into n +1 sub-frequency bands; wherein, the ith sub-band is:

as a possible implementation manner, the second processing module determines, according to the calculation precision of the frequency domain simulation of the very large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-band, the number m +1 of scanning frequency points extracted from each sub-band, where m +1 satisfies the following equation:

in the formula, R_m(f) For the accuracy of the calculation, F (f) is the true value of the frequency response of the integrated circuit at the frequency f,

is the maximum value of F (f), L_m(f) For the calculated value of the frequency response curve at the frequency f, the maximum value of F (f) in the sub-band is the maximum value of the frequency response of the frequency points at the left and right end points of the sub-band, i.e. the maximum value

As a possible implementation manner, in the second processing module, a frequency point corresponding to a zero point of the m +1 st-order chebyshev polynomial is set as a scanning frequency point of each sub-band, where a position formula of the zero point is:

in the formula (f)_kIn order to be the zero point,

corresponding to each sub-frequency band, the value range of the zero point is f_i-1＜f＜f_iThen, the position formula of the scanning frequency point is:

in the formula (f)_kIs the scanning frequency point.

The embodiment of the application has the following beneficial effects:

according to the method, the resonance frequency point and the frequency response of the very large scale integrated circuit within the preset frequency range are calculated by adopting a resonance calculation mode according to the calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and the frequency responses of the initial frequency point and the termination frequency point within the preset frequency range are calculated; dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end frequency point of each sub-frequency band; determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the preset calculation precision of the frequency domain simulation of the very large scale integrated circuit and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band; taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point, and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel; interpolating at the zero point of the m + 1-time Chebyshev polynomial by adopting an interpolation method based on the non-uniform frequency point and the frequency response of each sub-frequency band to form a frequency response curve of the super-large-scale integrated circuit in each sub-frequency band; the frequency response curves of all the sub-frequency bands are combined to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range, the non-uniform frequency points with less quantity meeting the calculation precision requirement can be extracted, the frequency response curve of the integrated circuit frequency domain simulation meeting the precision requirement in the preset frequency band can be quickly calculated, and the potential performance problem of the designed ultra-large scale integrated circuit is avoided being difficult to detect.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic flowchart of an embodiment of a method for extracting frequency response frequency points and calculating a response curve of an integrated circuit according to the present disclosure.

Fig. 2 is a schematic structural diagram of an embodiment of an integrated circuit frequency response frequency point extraction and response curve calculation device provided in the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail by embodiments with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, "a plurality" means two or more unless otherwise specified. In the description of the present invention, "first", "second", "third", "fourth", "fifth", and the like are used only for distinguishing one from another, and do not indicate the degree of importance, the order, and the like thereof.

Referring to fig. 1, an embodiment of the present application provides a method for extracting frequency response points and calculating a response curve of an integrated circuit, the method mainly includes:

step 100, calculating a resonant frequency point and a frequency response of the very large scale integrated circuit within a preset frequency range by adopting a resonance calculation mode according to a calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and calculating the frequency responses of an initial frequency point and a termination frequency point within the preset frequency range;

step 200, dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end frequency point of each sub-frequency band;

step 300, determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the calculation precision of the frequency domain simulation of the super-large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band;

step 400, taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point, and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel;

in step 400, since the frequency response calculations of all frequency points in this step are independent of each other, the calculations can be performed in a parallel manner using a shared memory or a distributed memory: calculating the frequency response of one frequency point simultaneously and independently through each process until the frequency responses of the ultra-large scale integrated circuit at all frequency points are calculated, and finally collecting the frequency responses of all frequency points through a main process to obtain the frequency responses of all sub-frequency bands at non-uniform frequency points; before parallel computing, the number of processes needs to be manually determined, and one process is taken as a main process;

step 500, based on the non-uniform frequency points and the frequency response thereof of each sub-band, interpolating at the zero point of the m + 1-time Chebyshev polynomial by an interpolation method to form a frequency response curve of the very large scale integrated circuit at each sub-band;

and step 600, combining the frequency response curves of all the sub-frequency bands to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range.

By adopting the method, the non-uniform frequency points with less quantity meeting the calculation precision requirement can be extracted, the frequency response curve of the frequency domain simulation of the integrated circuit meeting the precision requirement in the preset frequency band is quickly calculated, and the potential performance problem of the designed ultra-large scale integrated circuit which is difficult to detect is avoided.

It should be noted that if there is no resonant frequency point in the predetermined frequency band of the very large scale integrated circuit, n is 0. At this time, the preset frequency band does not need to be divided, and the preset frequency band is directly used as the sub-frequency band in the embodiment of the application to be processed. Under the general condition, n is greater than 0, the frequency response curve meeting the precision requirement is obtained by calculating the resonant frequency point and the frequency response of the very large scale integrated circuit within the preset frequency range and a series of processing in the embodiment, and the problem that the frequency domain simulation of the very large scale integrated circuit cannot be accurately simulated at the resonant frequency can be avoided.

As a possible implementation manner, in the step 200, dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonant frequency points, together with the start frequency point and the end frequency point, where the start frequency point, the n resonant frequency points, and the end frequency point sequentially form an end frequency point of each sub-frequency band, and the method includes: the n resonance frequency points are connected with the starting frequency point f_lowAnd a termination frequency point f_highIn descending order, denoted as f_low<f₁<…<f_n<f_highDividing the preset frequency band inton +1 sub-bands; wherein, the ith sub-band is:

as a possible implementation manner, in the step 300, the m +1 satisfies the following equation:

in the formula, R_m(f) For the accuracy of the calculation, F (f) is the true value of the frequency response of the integrated circuit at the frequency f,is the maximum value of F (f), L_m(f) The value of the calculated frequency response curve at the frequency f; wherein, usually, the maximum value of F (f) in the sub-band is the maximum value of the frequency response of the two end point frequency points around the sub-band, that is, the maximum value is the frequency response of the frequency point at the left and right end points of the sub-band

By adopting the method, the m +1 meets the equation (1), the calculated m +1 numerical value is smaller on the basis of meeting the specified calculation precision requirement, the number of the non-uniform frequency points extracted correspondingly is smaller, the reduction of the calculated amount of frequency point frequency response is facilitated, the frequency response curve of the frequency domain simulation of the integrated circuit in the preset frequency band is further calculated quickly, the error between the curve and the real frequency response curve is smaller, and the potential performance problem of the designed ultra-large scale integrated circuit is avoided being difficult to detect.

As a possible implementation manner, in the step 300, setting a frequency point corresponding to a zero point of the m +1 st-order chebyshev polynomial as a scanning frequency point of each sub-band, a position formula of the zero point is as follows:

in the formula (f)_kIn order to be the zero point,

corresponding to each sub-frequency band, the value range of the zero point is f_i-1＜f＜f_iThen, the position formula of the scanning frequency point is:

in the formula (f)_kIs the scanning frequency point.

It will be appreciated that if the function f (f) has a continuous derivative of order m +1 at [ -1,1], then when interpolating the polynomial f (f), the error produced by interpolating at the zero of the chebyshev polynomial of order m +1 is chosen to be minimal.

As a possible implementation manner, in the step 500, the interpolation method includes, but is not limited to: lagrange interpolation, barycentric lagrange interpolation, chebyshev polynomial interpolation, and newton interpolation.

As a possible implementation, the center-of-gravity Lagrange interpolation method is adopted to sub-frequency band f_i-1＜f＜f_iThe frequency domain response f (f) of (a) is polynomial interpolated, comprising:

step 510, calculating a gravity center weight, wherein a calculation formula of the gravity center weight is as follows:

in the formula, w_jThe weight of the center of gravity of the jth scanning frequency point is shown, and pi is the multiplication.

Step 520, define the sub-band f_i-1＜f＜f_iThe barycentric lagrange interpolation of the frequency domain response f (f) of (a) is:

wherein l (f) is an auxiliary polynomial of the formula:

step 530, for the sub-band f_i-1＜f＜f_iArbitrarily designated scanning frequency point f_sCalculating its frequency domain response F (F)_s) The fitting value of (a), the formula of the fitting value is:

as a possible implementation manner, the calculating, by using the resonance calculation mode, a resonance frequency point of the very large scale integrated circuit within a preset frequency band and a frequency response thereof includes: and writing a generalized eigenvalue equation of the continuity equation of the ultra-large scale integrated circuit field through a region discretization column by adopting a resonance calculation mode, solving the generalized eigenvalue equation to obtain a plurality of eigenvalues and eigenvectors, wherein the eigenvalues correspond to resonance frequency points of electromagnetic waves propagated in a dielectric layer of the integrated circuit under the passive condition of the ultra-large scale integrated circuit, the eigenvectors corresponding to each resonance frequency point correspond to the distribution of the field under the resonance frequency points, and the frequency response corresponding to the resonance frequency points is obtained according to the distribution of the field.

It should be noted that, in the step 100, a three-dimensional model of the frequency response of the integrated circuit at a frequency point in the frequency domain simulation of the very large integrated circuit is simplified to obtain a plurality of two-dimensional models, an electric field equation set of the corresponding two-dimensional models is established by a finite element analysis method, and finally, the electric field equation set is combined to obtain a total sparse matrix of the electric field equation set. The different fields and their external circuits are coupled to each other by vias because each field and its external circuit formed by each layer of integrated circuits is not an isolated electrical connection, and all fields ultimately form an integrated system.

However, the computational resources required for solving the three-dimensional model of the frequency response of the integrated circuit of one frequency in the frequency domain simulation of the very large scale integrated circuit by the three-dimensional method are huge, and the method is difficult to be used for really analyzing the complex very large scale integrated circuit system under the existing computational resources. However, as it can be known from the analysis of the dimension characteristics of the very large scale integrated circuit, in the frequency domain simulation of the very large scale integrated circuit, since the dimension of the actual PCB or chip package in the very large scale integrated circuit is much larger than the thickness and the distance between the boards, it can be known that the frequency domain simulation of the very large scale integrated circuit is not changed in the thickness direction of the boards, and therefore, it can be known that the problem that the three-dimensional equation needs to be solved can be solved by using an equation which is simplified into two dimensions, and therefore, in the step 100, the three-dimensional model can be simplified into the two.

In step 100, the distributions of dielectric constant, permeability μ, electric field strength E, and magnetic field strength H in a three-dimensional model of frequency response of a frequency in frequency domain simulation of a very large scale integrated circuit are all functions of three-dimensional space coordinates (x, y, z), that is: and (x, y, z), μ ═ μ (x, y, z), E ═ E (x, y, z), H ═ H (x, y, z). In the resonant mode, the function of the three-dimensional model satisfies the following equation:

where ω is the angular frequency of the integrated circuit simulation.

In step 100, when the actual PCB or chip package board size in the very large scale integrated circuit is much larger than the board thickness and the board spacing H, the three-dimensional model of the frequency response of a frequency point in the frequency domain simulation of the very large scale integrated circuit can be simplified into a two-dimensional model, and the distribution of dielectric constant, magnetic permeability μ, electric field strength E and magnetic field strength H in the model is a function of two-dimensional plane coordinates (x, y), that is: and (x, y), μ ═ μ (x, y), E ═ E (x, y), H ═ H (x, y), and the distribution is independent of z. And the potential u and the surface current density J in the field_sSatisfies the following conditions:

in the formulaUnit vectors representing directions x, y, z, respectively,E_zis the z-direction component of the electric field strength, H_xAnd H_yThe x and y directional components of the magnetic field strength, respectively.

Through the equivalence from the three-dimensional model to the two-dimensional model, the two-dimensional finite element functional extreme value formula corresponding to the two-dimensional model is obtained as follows:

in the formula (I), the compound is shown in the specification,is a functional, means to take an extreme value to the functional,

for the surface admittance of the grid cell i,

is a boundary_jIs determined by the constant of (a) and (b),is a normal vector of the cell surface, V is a boundary_jVolume of the corresponding grid cell, u_kIs a boundary_kThe distribution of the electric potential on the upper side,

indicating a position to the right of the boundary and infinitely close to the boundary,denotes the position to the left of the boundary and infinitely close to the boundary, Ω_iRepresenting the area of the cell i, Z_siIs the surface impedance of the grid cell i, u_iIs the potential of grid cell i.

With the extreme condition of equation (6), a system of eigenvalue equations for the resonant modes can be formed.

Referring to fig. 2, an embodiment of the present invention provides an apparatus for extracting frequency response points and calculating a response curve of an integrated circuit, the apparatus mainly comprising:

the resonance frequency point calculation module is used for calculating the resonance frequency point and the frequency response of the very large scale integrated circuit within a preset frequency range by adopting a resonance calculation mode according to the calculation requirement of the frequency response of the frequency domain simulation of the very large scale integrated circuit, and calculating the frequency responses of the initial frequency point and the termination frequency point within the preset frequency range;

the first processing module is used for dividing the preset frequency band into n +1 sub-frequency bands according to the calculated n resonance frequency points, the start frequency point and the end frequency point, wherein the start frequency point, the n resonance frequency points and the end frequency point sequentially form an end point frequency point of each sub-frequency band;

the second processing module is used for determining the number m +1 of scanning frequency points extracted from each sub-frequency band according to the calculation precision of the frequency domain simulation of the super-large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-frequency band, and setting the frequency point corresponding to the zero point of the m + 1-order Chebyshev polynomial as the scanning frequency point of each sub-frequency band;

the third processing module is used for taking the scanning frequency point of each sub-frequency band as an extracted non-uniform frequency point and calculating the frequency response of the ultra-large scale integrated circuit at the non-uniform frequency point in parallel;

a fourth processing module, configured to perform interpolation at a zero point of the m + 1-order chebyshev polynomial by using an interpolation method based on the non-uniform frequency point and the frequency response of the frequency sub-band, so as to form a frequency response curve of the very large scale integrated circuit in each frequency sub-band;

and the fifth processing module is used for combining the frequency response curves of all the sub-frequency bands to obtain the frequency response curve of the ultra-large scale integrated circuit in the whole preset frequency band range.

By adopting the device, the non-uniform frequency points with less quantity meeting the calculation precision requirement can be extracted, the frequency response curve of the frequency domain simulation of the integrated circuit meeting the precision requirement in the preset frequency band can be quickly calculated, and the potential performance problem of the designed ultra-large scale integrated circuit which is difficult to detect is avoided.

As a possible implementation manner, in the first processing module, the dividing, according to the calculated n resonant frequency points, the starting frequency point and the ending frequency point, the preset frequency band into n +1 sub-frequency bands, where the starting frequency point, the n resonant frequency points, and the ending frequency point sequentially form an endpoint frequency point of each sub-frequency band, includes: the n resonance frequency points are connected with the starting frequency point f_lowAnd a termination frequency point f_highIn descending order, denoted as f_low<f₁<…<f_n<f_highDividing the preset frequency band into n +1 sub-frequency bands; wherein, the ith sub-band is:

as a possible implementation manner, the second processing module determines, according to the calculation precision of the frequency domain simulation of the very large scale integrated circuit given in advance and the frequency response of the endpoint frequency point of each sub-band, the number m +1 of scanning frequency points extracted from each sub-band, where m +1 satisfies the following equation:

in the formula, R_m(f) For the accuracy of the calculation, F (f) is the true value of the frequency response of the integrated circuit at the frequency f,is the maximum value of F (f), L_m(f) The value of the calculated frequency response curve at the frequency f; wherein, usually, the maximum value of F (f) in the sub-band is the maximum value of the frequency response of the two end point frequency points around the sub-band, that is, the maximum value is the frequency response of the frequency point at the left and right end points of the sub-band

By adopting the device, the m +1 meets the equation (1), the calculated m +1 numerical value is smaller on the basis of meeting the specified calculation precision requirement, the number of the non-uniform frequency points extracted correspondingly is smaller, the reduction of the calculated amount of the frequency points is facilitated, the frequency response curve of the frequency domain simulation of the integrated circuit in the preset frequency band is further calculated quickly, the error between the curve and the real frequency response curve is smaller, and the potential performance problem of the designed ultra-large scale integrated circuit is avoided being difficult to detect.

As a possible implementation manner, in the second processing module, a frequency point corresponding to a zero point of the m +1 st-order chebyshev polynomial is set as a scanning frequency point of each sub-band, where a position formula of the zero point is:

in the formula (f)_kIn order to be the zero point,

corresponding to each sub-frequency band, the value range of the zero point is f_i-1＜f＜f_iThen, the position formula of the scanning frequency point is:

in the formula (f)_kIs the scanning frequency point.

The foregoing is considered as illustrative of the preferred embodiments of the invention and the technical principles employed. It will be understood by those skilled in the art that the present application is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the application. Therefore, although the present application has been described in more detail with reference to the above embodiments, the present application is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present application, and the scope of the present application is determined by the scope of the appended claims.