Pin capacitance dynamic estimation method and device of power consumption analysis tool, equipment and storage medium

Abstract

The invention discloses a pin capacitance dynamic estimation method and device for a power consumption analysis tool, equipment and a storage medium, and the method comprises the steps: recognizing a starting node of a circuit, carrying out the downward traversal of the circuit from the starting node, and determining a first instance which is inquired in the traversal process and is connected with the starting node as a target instance; starting from an output pin of the target instance, traversing and searching a fan-out instance connected with the output pin of the target instance, and calculating an output pin transition time value and an input pin capacitance value of the target instance; judging whether the fan-out instance meets a preset traversal termination condition or not, and independently calculating the output pin transition time value and the input pin capacitance value of each target instance found by traversal once to obtain more accurate capacitance value data closer to an actual value; and the accuracy and reliability of power consumption estimation in integrated circuit design are improved.

Description

Technical Field

[0001] The present application belongs to the technical field of integrated circuit design, and in particular, relates to a pin capacitance dynamic estimation method, device, equipment and storage medium of a power consumption analysis tool. Background Art

[0002] Electronic Design Automation (EDA) refers to the use of computer-aided design software to complete the design process of very large-scale integrated circuit (VLSI) chips. This process includes multiple stages such as functional design, synthesis, verification, physical design (such as layout, routing, layout, design rule checking, etc.). Common EDA tools include low-power static checking tools LPC and RTL-level power analysis tools RPA.

[0003] In the chip design process, power consumption analysis is crucial, and power consumption calculation is one of the core functions of related EDA tools (such as RTL-level power consumption analysis tools RPA). Accurate power consumption estimation can help chip designers evaluate power consumption performance in the early stages of design, and how to provide accurate power consumption estimation is crucial for chip designers.

[0004] In EDA power consumption analysis, capacitance value is a key factor affecting power consumption. Capacitance value directly affects flip power consumption (the main variable parameter in the calculation formula of flip power consumption), and indirectly affects internal power consumption by affecting signal flip speed. Therefore, accurate acquisition of capacitance value is crucial for power consumption estimation.

[0005] The prior art parses static capacitance parameters (such as capacitance values ​​recorded in capacitance fields) in a library file (liberty file) and directly uses them as input pin capacitance values ​​as the basis for power consumption estimation.

[0006] However, as semiconductor process nodes develop towards advanced nodes (such as 7nm and below), the parasitic effects of connections and devices become more complex, and the impact of dynamic changes in capacitance values ​​on power consumption estimation gradually becomes apparent. The deviation between traditional fixed capacitance values ​​and capacitance values ​​under actual working conditions increases sharply, making it impossible to accurately reflect the true behavior of the circuit, which in turn leads to a significant decrease in the accuracy of key power consumption calculation results such as flip power consumption and internal power consumption. Summary of the invention

[0007] The embodiments of the present application provide a method, apparatus, device and storage medium for dynamically estimating the pin capacitance of a power consumption analysis tool, aiming to solve the problem that the capacitance value calculation of existing power consumption analysis tools is not accurate enough and to improve the accuracy of the power consumption analysis tool in calculating the pin capacitance value.

[0008] On the one hand, an embodiment of the present application provides a pin capacitance dynamic estimation method of a power consumption analysis tool, comprising the following steps:

[0009] Identify a starting node of a circuit, traverse the circuit downward from the starting node, and determine the first instance connected to the starting node found during the traversal as a target instance;

[0010] Starting from the output pin of the target instance, traverse and search for the fan-out instance connected to the output pin of the target instance, and calculate the output pin transition time value and input pin capacitance value of the target instance;

[0011] Determine whether the fan-out instance satisfies a preset traversal termination condition; if the fan-out instance does not satisfy the traversal termination condition, determine the fan-out instance as the new target instance, and return to step: calculate the output pin transition time value and the input pin capacitance value of the target instance until the traversal termination condition is met.

[0012] On the other hand, an embodiment of the present application provides a pin capacitance dynamic estimation device of a power consumption analysis tool, comprising:

[0013] An identification module, used for identifying a starting node of a circuit, traversing the circuit downward from the starting node, and determining the first instance connected to the starting node found during the traversal as a target instance;

[0014] A calculation module, used for calculating an output pin transition time value and an input pin capacitance value of the target instance;

[0015] A traversal module is used to traverse along the output pin direction of the target instance to find the fan-out instance connected to the output pin, and determine whether the fan-out instance meets the preset traversal termination condition: when the fan-out instance does not meet the traversal termination condition, determine the fan-out instance as the new target instance, and return to the step of calculating the output pin transition time value and the input pin capacitance value of the target instance until the traversal termination condition is met.

[0016] On the other hand, an embodiment of the present application provides an electronic device, the electronic device comprising:

[0017] a processor and a memory storing computer program instructions;

[0018] When the processor executes the computer program instructions, the steps of the pin capacitance dynamic estimation method of the power consumption analysis tool in the above aspect are implemented.

[0019] On the other hand, an embodiment of the present application provides a computer-readable storage medium having computer program instructions stored thereon. When the computer program instructions are executed by a processor, the steps of the pin capacitance dynamic estimation method of the power consumption analysis tool in the above aspect are implemented.

[0020] On the other hand, an embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of the pin capacitance dynamic estimation method of the power consumption analysis tool in the above aspect are implemented.

[0021] The embodiment of the present application identifies the starting node of the circuit, traverses the circuit downward from the starting node, determines the first instance connected to the starting node found during the traversal process as the target instance, and starts from the output pin of the target instance, traverses and searches for the fan-out instance connected to the output pin of the target instance, and determines whether the fan-out instance meets the preset traversal termination condition: if the fan-out instance does not meet the traversal termination condition, the fan-out instance is determined as a new target instance, and returns to the step: calculate the output pin transition time value and input pin capacitance value of the target instance until the traversal termination condition is met. Compared with the method of directly calling the library file to pre-store static parameters in the prior art, this method performs an independent calculation of the output pin transition time value and input pin capacitance value of each target instance found through the traversal, which can effectively solve the parasitic parameter coupling effect between the unit devices with direct input and output connections, thereby obtaining more accurate capacitance value data that is closer to the actual value, and improving the accuracy and reliability of power consumption estimation in integrated circuit design. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 It is a flowchart of a pin capacitance dynamic estimation method of a power consumption analysis tool provided by an embodiment of the present application;

[0024] Figure 2 It is a circuit structure diagram of a pin capacitance dynamic estimation method of a power consumption analysis tool provided by an embodiment of the present application;

[0025] Figure 3 is a structural schematic diagram of a pin capacitance dynamic estimation device of a power consumption analysis tool provided by another embodiment of the present application;

[0026] Figure 4 It is a structural schematic diagram of an electronic device of a pin capacitance dynamic estimation method of a power consumption analysis tool provided by another embodiment of the present application. DETAILED DESCRIPTION

[0027] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0029] Electronic Design Automation (EDA) refers to the use of computer-aided design software to complete the design process of very large-scale integrated circuit (VLSI) chips. This process includes multiple stages such as functional design, synthesis, verification, physical design (such as layout, routing, layout, design rule checking, etc.). Common EDA tools include low-power static checking tools LPC and RTL-level power analysis tools RPA.

[0030] In the chip design process, power consumption analysis is crucial, and power consumption calculation is one of the core functions of related EDA tools (such as RTL-level power consumption analysis tools RPA). Accurate power consumption estimation can help chip designers evaluate power consumption performance in the early stages of design, and how to provide accurate power consumption estimation is crucial for chip designers.

[0031] In EDA power consumption analysis, capacitance value is a key factor affecting power consumption. Capacitance value directly affects flip power consumption (the main variable parameter in the calculation formula of flip power consumption), and indirectly affects internal power consumption by affecting signal flip speed. Therefore, accurate acquisition of capacitance value is crucial for power consumption estimation.

[0032] The capacitance value is the main variable parameter in the calculation formula of switching power consumption, and the capacitance value will directly affect the switching power consumption. Among them, switching power consumption (Switching Power) is an important part of integrated circuit design and power consumption calculation. It refers to the energy consumed when the output state of the logic gate or other digital circuit elements in the integrated circuit changes. In EDA (electronic design automation) software, switching power consumption is closely related to the final power analysis results. The calculation formula for switching power consumption in digital circuits is P=α*C*V²*f, where: P represents switching power consumption; α represents the activity factor, which represents the probability of the node jumping from 0 to 1, usually set to 0.5; C is the total capacitance; V is the power supply voltage; f is the clock frequency. EDA software usually needs to obtain relevant data from SPEF files, Liberty files, and simulation files, and then substitute it into the switching power consumption calculation formula to calculate the switching power consumption of the circuit.

[0033] Capacitance is also the main variable parameter for calculating internal power consumption. Internal power consumption refers to the power consumed by the short-circuit current between the power supply and the ground during the brief period when the PMOS and NMOS tubes are turned on at the same time during the flipping process of the CMOS logic gate. This short-circuit current will flow directly from VDD to the ground, causing energy loss. The capacitance value indirectly affects the internal power consumption mainly by affecting the flipping speed of the signal.

[0034] In the related art, when determining the capacitance value of the input pin, the static capacitance parameters (such as the capacitance value recorded in the capacitance field) in the library file (liberty file) are usually parsed and directly used as the input pin capacitance value as the basis for power consumption estimation, which has a certain effect in design scenarios with low power consumption accuracy requirements. However, in the actual circuit operation process, the pin capacitance value will change dynamically, although the result obtained by calculating with a fixed capacitance value is acceptable in application scenarios where the power consumption estimation accuracy requirements are not high.

[0035] However, as semiconductor process nodes develop towards advanced nodes (such as 7nm and below), the parasitic effects of connections and devices become more complex, and the impact of dynamic changes in capacitance values ​​on power consumption estimation gradually becomes apparent. The deviation between traditional fixed capacitance values ​​and capacitance values ​​under actual working conditions increases sharply, making it impossible to accurately reflect the true behavior of the circuit, which in turn leads to a significant decrease in the accuracy of key power consumption calculation results such as flip power consumption and internal power consumption.

[0036] In summary, the pin capacitance dynamic estimation method of the power consumption analysis tool in the related art has problems such as insufficient accuracy, large deviation between the capacitance estimation result and the actual capacitance value, and poor credibility of the error amplification calculation result under advanced processes.

[0037] In order to solve at least one of the above technical problems, an embodiment of the present application provides a pin capacitance dynamic estimation method, device, equipment and storage medium of a power consumption analysis tool. The pin capacitance dynamic estimation method of the power consumption analysis tool of an embodiment of the present application is first introduced with reference to the accompanying drawings.

[0038] Figure 1 An optional flow chart of a pin capacitance dynamic estimation method of a power consumption analysis tool according to an embodiment of the present application is shown. In this example, the method may include the following steps:

[0039] S110, identifying a starting node of the circuit, traversing the circuit downward from the starting node, and determining the first instance connected to the starting node found during the traversal as a target instance;

[0040] S120, starting from the output pin of the target instance, traverse and search for the fan-out instance connected to the output pin of the target instance, and calculate the output pin transition time value and input pin capacitance value of the target instance;

[0041] S130, determining whether the fan-out instance satisfies a preset traversal termination condition. If the fan-out instance does not satisfy the traversal termination condition, determining the fan-out instance as a new target instance, and returning to step: starting from the output pin of the target instance, traversing and searching for the fan-out instance connected to the output pin of the target instance, calculating the output pin transition time value and the input pin capacitance value of the target instance, until the traversal termination condition is satisfied.

[0042] In this embodiment, by identifying the starting node of the circuit, the circuit is traversed downward from the starting node, the first instance connected to the starting node found during the traversal process is determined as the target instance, and starting from the output pin of the target instance, the fan-out instance connected to the output pin of the target instance is traversed to determine whether the fan-out instance meets the preset traversal termination condition: if the fan-out instance does not meet the traversal termination condition, the fan-out instance is determined as a new target instance, and the step of returning to: calculating the output pin transition time value and input pin capacitance value of the target instance until the traversal termination condition is met. Compared with the method of directly calling the library file to pre-store static parameters in the prior art, this method performs an independent calculation of the output pin transition time value and input pin capacitance value of each target instance found through the traversal, which can effectively solve the parasitic parameter coupling effect between the unit devices directly connected to the input and output, thereby obtaining more accurate capacitance value data that is closer to the actual value, and improving the accuracy and reliability of power consumption estimation in integrated circuit design.

[0043] In S110, the starting node of the circuit is the main input port of the circuit, that is, the input of the top-level module. When performing power consumption analysis or other circuit analysis, the EDA tool usually traverses the entire circuit from the starting node, that is, starting from the starting node, and analyzing the circuit connection relationship step by step along the propagation direction of the signal from input to output, and determines the first instance directly connected to the starting node found during the traversal process as the target instance. The above target instance is a specific object after the unit device is instantiated. The behavior and parameters of the unit corresponding to the target instance are recorded in the library file, and the input pin of the first target instance connected to the starting node is connected to the starting node.

[0044] In S120, the fan-out instance connected to the output pin is traversed along the output pin direction of the target instance, and the output pin transition time value and input pin capacitance value of the target instance are calculated. Specifically, it includes: calculating and updating the output pin transition time value of the target instance according to the input pin capacitance value of the fan-out instance connected to the target instance; at the same time, calculating and updating the input pin capacitance value of the target instance according to the output pin transition time value of the upper-level instance connected to the input pin of the target instance. Among them, the fan-out instance is a lower-level instance connected to the target instance and receiving the target instance signal, and the circuit signal is directly connected from the target instance output pin to the input pin of the fan-out instance. After finding the fan-out instance connected to the output pin of the target instance, the step of calculating the output pin transition time value and input pin capacitance value of the target instance is performed, wherein the output pin transition time value of the target instance is the time required for the output signal on the output pin of the target instance to jump from a high level to a low level (or vice versa), and the input pin capacitance value of the target instance refers to the load capacitance presented by the input pin of the target instance to the previous circuit. Each time the calculation of the output pin transition time value and the input pin capacitance value of the target instance is performed, the output pin transition time value and the input pin capacitance value of the target instance are updated once, and the accuracy is improved once.

[0045] In S130, it is determined whether the fan-out instance satisfies the preset traversal termination condition. When the fan-out instance does not satisfy the traversal termination condition, the fan-out instance is determined as a new target instance, and the process returns to step: calculating the output pin transition time value and the input pin capacitance value of the target instance until the traversal termination condition is satisfied. If the fan-out instance satisfies the preset traversal termination condition, the traversal is stopped.

[0046] It should be noted that the traversal termination condition in this embodiment is that the fan-out instance does not have a next-level instance, that is, in the hierarchy of the circuit, the output pin of the fan-out instance is not connected to any subsequent logic unit or instance. In other words, the output pin of the fan-out instance has no further fan-out target. In other embodiments, the traversal termination condition may also include: the output pin of the fan-out instance is connected to the final node of the circuit, wherein the final node refers to the primary output port (primitive output) of the circuit, and the primary output port of the circuit is usually the output port of the top-level module, indicating that the traversal has reached the end of the circuit.

[0047] If the fan-out instance does not meet the traversal termination condition, it indicates that the fan-out instance still has a next-level instance, and the output pin of the current fan-out instance is connected to the input pin of the next-level instance, and the output pin transition time value of the current fan-out instance can continue to be calculated or updated. If the fan-out instance meets the traversal termination condition, it indicates that the current fan-out instance no longer has a next-level instance, and there is no need to perform separate calculation and update of the output pin transition time value.

[0048] After the above steps, the output pin transition time value and input pin capacitance value of each target instance found by the traversal are calculated, and the fan-out instance that meets the traversal termination condition no longer has the next-level instance or pin connection and association relationship. Therefore, when the fan-out instance meets the traversal termination condition, the output pin transition time value of the target instance that can be calculated in the circuit or the input pin capacitance value of the fan-out instance has completed a calculation and data update based on the pin connection relationship.

[0049] As an optional implementation manner, the above S120 may include:

[0050] S210, calculate the output pin transition time value of the target instance based on the pin transition time lookup table, the input pin transition time value and the output pin capacitance value, wherein the pin transition time lookup table includes several index capacitance values, index transition time values ​​and result transition time values ​​corresponding to the index capacitance values ​​and the index transition time values.

[0051] Among them, the pin transition time lookup table records a number of index capacitance values, index transition time values ​​and result transition time values ​​that match the two at the same time. The pin transition time lookup table is stored in a library file in a tabular form. Usually, the above-mentioned index capacitance values, index transition time values ​​and corresponding result transition time values ​​are obtained by pre-measurement or estimation and pre-stored in the pin transition time lookup table of the library file. In the pin transition time lookup table, the index capacitance value, index transition time value and the result transition time value that matches the two at the same time are recorded and saved in a mapping manner, that is, the index capacitance value and the index transition time value are used as query indexes, and the result transition time value is used as output value, which is used for fast search and call.

[0052] The following is an example of a pin transition time lookup table in a library file. The pin transition time lookup table is an 8x8 lookup table recorded in the library file using 8 index capacitor values ​​and 8 index transition time values. In the pin transition time lookup table, the value that matches both the index transition time value and the index capacitor value is the resulting transition time value.

[0053] {

[0054] rise_transition(delay_template_8x8){

[0055] index_1("0.001,0.00218134,0.00475826,0.0103794,0.022641,0.0493878,0.107732,0.235");

[0056] index_2("0.0002,0.000605044,0.00183039,0.00553733,0.0167516,0.0506773,0.15331,0.463796");

[0057] values(\

[0058] "0.00114123,0.00131873,0.0018541,0.00347308,0.00843215,0.023489,0.0690331,0.206894",\

[0059] "0.00125902,0.00144143,0.00198726,0.00359838,0.00848276,0.0234904,0.0690824,0.206894",\

[0060] "0.00183995,0.00202087,0.00244541,0.00390126,0.00875883,0.0236118,0.0691211,0.206911",

[0061] "0.00269243,0.00293168,0.00356908,0.0051868,0.00946834,0.0241446,0.0692052,0.206952",\

[0062] "0.00417516,0.00447807,0.00532775,0.00737574,0.0121709,0.0255245,0.0700324,0.207179",\

[0063] "0.00678458,0.00720175,0.00836044,0.0110551,0.0172148,0.0307391,0.0731649,0.208546",

[0064] "0.0112102,0.0118703,0.0135684,0.0174393,0.0255759,0.04277,0.0823884,0.214792",\

[0065] "0.0188822,0.0198724,0.0224221,0.0283273,0.0401332,0.0627177,0.110373,0.230139"\ );

[0067] }

[0068] S220, calculating the input pin capacitance value of the target instance based on the pin receiving capacitance lookup table, the input pin transition time value and the output pin capacitance value, wherein the pin receiving capacitance lookup table includes a number of index capacitance values, index transition time values ​​and result capacitance values ​​corresponding to the index capacitance values ​​and the index transition time values.

[0069] Among them, the pin receiving capacitance lookup table records a number of index capacitance values, index transition time values ​​and result capacitance values ​​that match the two at the same time. The pin receiving capacitance lookup table is stored in a library file in a tabular form. Usually, the above-mentioned index capacitance values, index transition time values ​​and corresponding result capacitance values ​​are obtained by pre-measurement or estimation and pre-stored in the pin receiving capacitance lookup table of the library file. In the pin receiving capacitance lookup table, the index capacitance value, index transition time value and result capacitance value that match the two at the same time are recorded and saved in a mapping manner, that is, the index capacitance value and the index transition time value are used as query indexes, and the result capacitance value is used as the output value, which is used for fast search and call.

[0070] The following is an example of a pin receiving capacitance lookup table in the library file. The pin receiving capacitance lookup table is an 8x8 lookup table used in the library file to record the rising edge transition time. The value in the lookup table that matches the index transition time value and the index capacitance value is the result capacitance value.

[0071] receiver_capacitance2_rise(delay_template_8x8){

[0072] index_1("0.00110331,0.00252549,0.00579461,0.0132797,0.0304333,0.0697445,0.159636,0.3663");

[0073] index_2("0.0002,0.000435398,0.000947858,0.00206348,0.00449217,0.00977942,0.0212897,0.0463475");

[0074] values(

[0075] "0.000452041,0.000451034,0.000452721,0.000453121,0.000453398,0.000453556,0.000453637,0.000453676",

[0076] "0.000456561,0.000456281,0.000456101,0.000456081,0.000456139,0.000456196,0.000456235,0.000456254",

[0077] "0.000456341,0.00045611,0.000455779,0.000455496,0.000455352,0.000455302,0.000455287,0.000455283",

[0078] "0.000458533,0.000458491,0.000458386,0.000458195,0.000458013,0.000457903,0.000457853,0.000457631",

[0079] "0.000461542,0.000481492,0.000481404,0.000481273,0.000481106,0.000480963,0.000480873,0.000480828",

[0080] "0.00054815,0.000548105,0.000548015,0.000547859,0.000547648,0.000547436,0.000547276,0.000547181",

[0081] "0.000705836,0.000705727,0.000705541,0.00070527,0.000704936,0.000704598,0.00070433,0.000704158",

[0082] "0.000909726,0.000923845,0.000940908,0.000956544,0.000967852,0.000974296,0.000977492,0.000975777" );

[0084] }

[0085] As an optional implementation, please refer to Figure 2, taking the process of calculating the input pin capacitance value of the target instance i3 as an example, first determine the upper level instance i1 connected to the target instance i3, the input pin i3 / A of the target instance is connected to the upper level instance i1 through the wire net n1, and the transition time value of the output pin i1 / Z corresponding to the upper level instance i1 is determined as the input pin transition time value of the input pin i3 / A of the target instance, and then determine the output pin capacitance value of the output pin i3 / Z of the target instance i3 through the input pin capacitance value of the fan-out instance of the target instance, wherein the fan-out instance of the target instance i3 is the lower level instance connected to the target instance through the wire net n3.

[0086] After determining the input pin transition time value of the input pin, the input pin transition time value and the output pin capacitance value of the above target instance are substituted into the pin transition time lookup table, and the resulting capacitance value obtained by the query is used as the final input pin capacitance value of the input pin of the target instance, replacing the fixed capacitance value recorded in the library file used in the prior art, so as to improve the accuracy of the input pin capacitance value of the target instance, and improve the calculation accuracy in the subsequent calculation of other parameters associated with the output pin transition time value.

[0087] Similarly, if it is necessary to calculate the input pin capacitance values ​​of other input pins of the target instance, for example, if you want to find another input pin capacitance value i3 / B of the target instance, first determine the upper-level instance i2 to which the input pin i3 / B of the target instance is connected. The input pin i3 / B of the target instance is connected to the upper-level instance i2 through the wire net n4, and then determine the output pin transition time value i2 / Z of the upper-level instance i2 as the input pin transition time value of the input pin i3 / B of the target instance.

[0088] Correspondingly, the step of calculating the output pin transition time value of the target instance includes: first determining the input pin transition time value of the target instance, then determining the output pin capacitance value of the target instance, substituting the above input pin transition time value and output pin capacitance value into the pin receiving capacitance lookup table, and using the resulting transition time value as the output pin transition time value corresponding to a final output pin of the target instance, so as to improve the accuracy of the output pin transition time value of the target instance, and improve the calculation accuracy when subsequently calculating other parameters associated with the output pin transition time value.

[0089] Before executing step S120, that is, before the step of calculating the output pin transition time value and the input pin capacitance value of the target instance, the step of electronic design automation software reading and loading the library file is also included to obtain data such as the pin transition time lookup table and the pin receiving capacitance lookup table. The library file is usually written in accordance with the industry standard "Liberty User Guides and Reference Manual". The library file usually has a .lib extension and can also be called a "Liberty file". The library file is used to describe the timing characteristics, capacitance value, power consumption and other parameters of the logic unit in detail to support the design and analysis of subsequent circuits, including fixed capacitance value (pin capacitance), pin transition time lookup table, pin receiving capacitance lookup table and other data.

[0090] Compared with the traditional method of directly using fixed values ​​or default values, this embodiment can calculate more accurate input pin capacitance values ​​and output pin transition time values ​​of the target pin by table lookup, and add parameter changes of associated pins of the upper-level instance or the lower-level instance that have a connection relationship with the input pin or output pin of the target instance for separate calculation. Combined with the query method of the lookup table pre-stored in the library file, it more accurately reflects the characteristics of the pin capacitance value and transition time value changing with the working conditions, thereby reducing the error caused by model simplification, and improving the accuracy and reliability of key design links such as integrated circuit power consumption analysis and timing analysis. In addition, the table lookup method also has the technical effect of fast calculation speed.

[0091] As an optional implementation manner, before the above S120, the following may also be included:

[0092] S310, when the input pin of the target instance is connected to the starting node, the input pin transition time value of the input pin is configured as the initial transition time value preset by the user; when the input pin is connected to the output pin of other instances, the input pin transition time value is the output pin transition time value of the upper-level instance connected to the input pin.

[0093] In step S310, in order to more accurately calculate the output pin transition time value and input pin capacitance value of the target instance, a step of initializing the input pin transition time value of the target instance is also included. Specifically, when the target instance is a next-level instance directly connected to the top-level module, at this time, the input pin of the target instance receives a signal from the output port of the top-level module, and the input pin transition time value of the target instance will be configured as the initial transition time value preset by the user. If the user does not pre-set the initial transition time value separately, the default initial transition time value of 0 is used.

[0094] When the input pin of the target instance is connected to the output pin of other instances, that is, the input pin of the target instance is not directly connected to the starting node, but is connected to the output pin of other instances in the circuit (that is, the previous instance), at this time the input pin of the target instance receives the output signal from the previous instance, and the input pin transition time value of the input pin of the target instance will directly adopt the output pin transition time value of the previous instance connected to the input pin of the target instance.

[0095] By adopting the output pin transition time value of the previous level instance as the input pin transition time value of the current target instance, the problem that the input signal transition time value of the next level instance will be affected by the output signal transition time value of the previous level instance is solved. This can more truly reflect the transmission and change characteristics of the signal in the circuit, and provide more accurate input parameters for the subsequent calculation of the output pin transition time value and the input pin capacitance value.

[0096] As an optional implementation manner, before the above S120, the following may also be included:

[0097] S320, the output pin capacitance value of the target instance is configured as the input pin capacitance value of the fan-out instance connected to the output pin. During the first calculation, the input pin capacitance value of the fan-out instance is configured as the fixed input pin capacitance value preset for the fan-out instance in the library file.

[0098] In step S320, in order to more accurately calculate the output pin transition time value and input pin capacitance value of the target instance, the step of initializing and configuring the output pin capacitance value of the target instance is also included. Specifically, for each fan-out instance found by traversal, the input pin capacitance value of its input pin is obtained, and the input pin capacitance value of the fan-out instance is set as the output pin capacitance value of the target instance. Wherein, the fan-out instance refers to the next level instance whose input pin is connected to the output pin of the target instance. When the calculation is performed for the first time, since the input pin capacitance value of the fan-out instance has not been calculated separately, at this time, the input pin capacitance value of the fan-out instance can be configured as the input pin fixed capacitance value preset for the fan-out instance in the library file. Wherein, the input pin fixed capacitance value is the estimated capacitance reference value of the input pin pre-recorded in the relevant field of the library file, which is used to characterize the basic capacitance characteristics of the input pin under static conditions. The capacitance field is usually used in the library file to store this information. The EDA software can extract the input pin fixed capacitance value of the fan-out instance from the capacitance field after parsing the library file.

[0099] As an example, after calculating the output pin capacitance value of the target instance for the first time, the input pin fixed capacitance value for the fan-out instance can be obtained from the library file, for example: the input pin A1 of the fan-out instance has a pre-defined input pin fixed capacitance value of 0.000481018, and the above input pin fixed capacitance value is set as the output pin capacitance value of the target instance. Subsequently, as the iterative calculation proceeds, the input pin capacitance value of the fan-out instance can be calculated and updated based on the pin receiving capacitance lookup table, the input pin transition time value and the output pin capacitance value.

[0100] In some embodiments, the output pin of the target instance may be connected to the input pin of one or more fan-out instances, and the output pin capacitance value of the target instance may be configured as the sum of the input pin capacitance values ​​of all fan-out instances connected thereto. Specifically, when there are multiple fan-out instances connected to the output pin of the target instance, the output pin capacitance value of the target instance may be configured as the sum of the input pin capacitance values ​​of the input pins of all fan-out instances connected to the output pin of the target instance, that is, the sum of the input pin capacitance values ​​of all fan-out instances connected to the output pin of the target instance is calculated, and then the sum is used as the output pin capacitance value of the target instance.

[0101] In some embodiments, the output pin capacitance value of the target instance is configured to be the sum of the input pin capacitance values ​​of all fan-out instances connected to it, plus the sum of the connection capacitance values ​​of the connection between the output pin of the target instance and the input pin of the fan-out pin. The above method can more accurately evaluate the actual total load capacitance of the output pin of the target instance, and provide more accurate input parameters for subsequent capacitance value and transition time calculations.

[0102] It is worth noting that the related prior art extracts the above-mentioned input pin fixed capacitance value usually by directly setting it as other associated output pin capacitance values, while the purpose of obtaining the input pin fixed capacitance value in this embodiment is to serve as the data basis for calculating or searching the transition time in subsequent steps, and finally obtains the accurate output pin capacitance value calculation result after secondary calculation in combination with the pin transition time lookup table or the pin receiving capacitance lookup table, rather than extracting the input pin fixed capacitance value from the pin field of the library file and directly using it as the output pin capacitance value of the target instance for power consumption calculation.

[0103] Through the above method, the problem of inconsistency between the output pin capacitance value of the target instance and the input pin capacitance value of the next-level instance is solved, which can more truly reflect the transmission and change characteristics of the signal in the circuit, and provide more accurate input parameters for subsequent power consumption analysis. In addition, after the input pin capacitance value of the fan-out instance is updated with the iterative calculation, when the output pin of the target instance is calculated next time, the input pin capacitance value of the fan-out instance after the previous round of update can be used to configure a more accurate output pin capacitance value for the target instance, so as to improve the accuracy of subsequent power consumption calculation.

[0104] As an optional implementation, the above S120 may include: when there are index transition time values ​​and index capacitance values ​​that match both the input pin transition time value and the output pin capacitance value in the pin transition time lookup table or the pin receiving capacitance lookup table, determining the result transition time value that matches both the input pin transition time value and the output pin capacitance value in the pin transition time lookup table as the output pin transition time value of the target instance, or determining the result capacitance value that matches both the input pin transition time value and the output pin capacitance value in the pin receiving capacitance lookup table as the input pin capacitance value of the target instance.

[0105] In this embodiment, after the input pin transition time value or output pin capacitance value of the target instance is given, if the provided input pin transition time value or output pin capacitance value can find an exactly matching index transition time value and index capacitance value in the lookup table, the result capacitance value or result transition time value corresponding to the matching item is directly returned, and the result capacitance value or result transition time value is used to update the corresponding input pin transition time value or output pin capacitance value, so as to realize fast query and obtain accurate data.

[0106] As an optional implementation, the above S120 may include: when there is no index transition time value that completely matches the input pin transition time value or an index capacitance value that completely matches the output pin capacitance value in the pin transition time lookup table or the pin receiving capacitance lookup table, selecting two adjacent index transition time values ​​that are closest to the input pin transition time value or two adjacent index capacitance values ​​that are closest to the output pin capacitance value, constructing a linear interpolation formula based on the result transition time value or result capacitance value corresponding to the index transition time value or index capacitance value in the pin transition time lookup table or the pin receiving capacitance lookup table, substituting the input pin transition time value or the output pin capacitance value into the linear interpolation formula to calculate the interpolation transition time value or the interpolation capacitance value, and determining the calculated interpolation transition time value or interpolation capacitance value as the result transition time value or the result capacitance value.

[0107] In this embodiment, when the input pin transition time value and the output pin capacitance value cannot completely match the index value in the lookup table, a linear interpolation method is used to calculate the corresponding interpolation result. The specific steps include: first, in response to the input request of the input pin transition time value and the output pin capacitance value, a search is performed in the pre-stored pin transition time lookup table or the pin receiving capacitance lookup table to see whether there is an item that completely matches the input value. If a completely matching item is found, the corresponding transition time value or capacitance value is directly returned. If there is no completely matching item in the lookup table, the two adjacent index values ​​closest to the input value are selected, and a linear interpolation formula is constructed based on the two known index values ​​and their corresponding transition time values ​​or capacitance values. Subsequently, the linear interpolation formula is used to substitute the input pin transition time value or the output pin capacitance value into the linear interpolation formula to calculate the interpolated transition time value or the interpolated capacitance value, and it is determined as the result transition time value or the result capacitance value. Finally, the calculated input pin transition time value or the output pin capacitance value is returned and used in subsequent calculation processes.

[0108] As an example, first, it is determined that the input pin transition time value T=0.013710 is between two known index transition time values ​​T4=0.0122878 and T5=0.0274411 according to the pin receiving capacitance lookup table. At this time, the two index transition time values ​​(T4 and T5) closest to the input pin transition time value T=0.013710 and the corresponding capacitance values ​​C4 and C5 are selected. Next, according to T4 and T5 and the corresponding capacitance values ​​C4 and C5, a linear interpolation formula is constructed using linear interpolation, where the independent variable of the linear interpolation formula is the index capacitance value (C), and the dependent variable is the transition time value (T). The linear interpolation formula can be expressed as: C=[(T-T4) / (T5-T4)]·(C5-C4)+C4. Finally, substitute the input pin transition time value into the above linear interpolation formula: C=[(0.013710-0.0122878) / (0.0274411-0.0122878)]·(0.000745305-0.000611997)+0.000611997, and get the interpolation capacitance value C=0.000624508, and use the interpolation capacitance value as the result capacitance value of the pin receiving capacitance lookup table.

[0109] This embodiment searches for the input pin transition time value and the output pin capacitance value. When there is no completely matching item in the lookup table, the estimated capacitance value or transition time value is obtained by selecting the two adjacent values ​​closest to the input value and using a linear interpolation formula for calculation. In the case where the lookup table items do not completely match, an estimation result with accuracy and precision can still be obtained.

[0110] As an optional implementation, the above S120 may include: the number of input pins of the target instance is one or more, and the number of output pins of the target instance is one or more. When the number of input pins or output pins of the target instance is multiple, the output pin transition time value or input pin capacitance value of each output pin or input pin of the target instance is calculated.

[0111] In an actual circuit, the target instance may have a single or multiple input pins or output pins. Therefore, when the target instance has multiple input pins or output pins, calculation is performed on each input pin or output pin in turn to calculate the output pin transition time value or input pin capacitance value of each output pin or input pin of the target instance, thereby accurately estimating the transition time value or capacitance value of each pin to ensure the accuracy and reliability of the results.

[0112] As an implementation manner, before step S110, the method further includes:

[0113] Determine the target number of iterations and the current number of iterations of the circuit, where the initial value of the current number of iterations is 0. After the traversal termination condition is met, the count value of the current number of iterations is incremented by 1, and it is determined whether the current number of iterations is equal to the target number of iterations. If the current number of iterations is less than the target number of iterations, return to identify the starting node of the circuit, traverse the circuit downward from the starting node, and determine the first instance connected to the starting node queried during the traversal process as the target instance.

[0114] Specifically, before the traversal begins, the steps of initializing the current number of iterations and the target number of iterations are included, wherein the current number of iterations is initialized to 0, and the target number of iterations is initialized to 2 by default according to the parameters set by the user.

[0115] After the traversal termination condition is met, the count value of the current iteration number is incremented by 1, and the current iteration number is compared with the target iteration number to determine whether the current iteration number is equal to the target iteration number; if the current iteration number is less than the target iteration number, return to the step of executing S110, that is, return to the step of identifying the starting node of the circuit, traverse the circuit downward from the starting node, and determine the first instance connected to the starting node found during the traversal process as the target instance. If the current iteration number is equal to the target iteration number, it indicates that the specified traversal iteration number has been reached, and the traversal is stopped.

[0116] It should be noted that in each iteration process, the traversal starts from the target instance and the output pin transition time value and input pin capacitance value of the target instance are calculated and updated, and the next level instance connected to the current target instance is continued to be obtained as the fan-out instance. If the traversal termination condition is not met, the fan-out instance is determined as the new target instance and its output pin transition time value and input pin capacitance value are calculated and updated.

[0117] During the first iteration, the output pin capacitance value or input pin transition time value corresponding to the target instance and the fan-out instance is configured as the initial value. For each traversed target instance, the steps of calculating the output pin transition time value of the target instance and the input pin capacitance value of the target instance are mainly through the pin transition time lookup table and the pin receiving capacitance lookup table. With the help of this new calculation method, the first update and improvement of the accuracy and precision of the output pin transition time value and input pin capacitance value data of the target instance is achieved.

[0118] During the second iteration, since the output pin capacitance value or input pin transition time value corresponding to the target instance and the fan-out instance is configured as the input pin capacitance value of the fan-out instance connected to the output pin or the output pin transition time value of the upper-level instance connected to the input pin, and the above-mentioned input pin capacitance value and output pin transition time value have been calculated and updated once in the previous iteration, the second iteration actually uses the updated and more accurate input pin capacitance value and output pin transition time value as the new calculation initial value, and adds the new calculation method of using the pin transition time lookup table and the pin receiving capacitance lookup table, which can further improve the accuracy of the output pin transition time value and the input pin capacitance value data.

[0119] Based on the same inventive concept, the present application also provides a pin capacitance dynamic estimation device for a power consumption analysis tool. Figure 3 Provide detailed explanation.

[0120] Figure 3 1 is a schematic diagram of the structure of a pin capacitance dynamic estimation device 300 of a power consumption analysis tool provided in an embodiment of the present application.

[0121] like Figure 3 As shown, the pin capacitance dynamic estimation device of the power consumption analysis tool may include:

[0122] An identification module 301 is used to identify a starting node of a circuit, traverse the circuit downward from the starting node, and determine the first instance connected to the starting node found during the traversal process as a target instance;

[0123] A calculation module 302 is used to traverse along the output pin direction of the target instance to find the fan-out instance connected to the output pin, and calculate the output pin transition time value and input pin capacitance value of the target instance;

[0124] The traversal module 303 determines whether the fan-out instance satisfies the preset traversal termination condition: when the fan-out instance does not satisfy the traversal termination condition, the fan-out instance is determined as a new target instance, and returns to the step of calculating the output pin transition time value and the input pin capacitance value of the target instance until the traversal termination condition is satisfied.

[0125] Figure 4 A schematic diagram of the hardware structure of an electronic device of a pin capacitance dynamic estimation method of a power consumption analysis tool provided in an embodiment of the present application is shown. The electronic device may be at least one of a computer, a server, and a document generation dedicated device. The electronic device includes a processor 1001 and a memory 1002 storing computer program instructions.

[0126] Specifically, the processor 1001 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0127] The memory 1002 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 1002 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. Where appropriate, the memory 1002 may include a removable or non-removable (or fixed) medium. Where appropriate, the memory 1002 may be inside or outside the electronic device. In a particular embodiment, the memory 1002 is a non-volatile solid-state memory.

[0128] The memory 1002 may include a read-only memory (ROM), a flash memory device, a random access memory (RAM), a magnetic disk storage media device, an optical storage media device, an electrical, optical or other physical / tangible memory storage device. Thus, typically, the memory 1002 includes a tangible (non-transitory) computer-readable storage medium (e.g., a memory device) of one or more software that may be encoded with computer-executable instructions and that, when executed (e.g., by one or more processors), is operable to perform the operations described with reference to the methods according to the above aspects of the present disclosure.

[0129] The processor 1001 reads and executes the computer program instructions stored in the memory 1002 to implement the steps of the pin capacitance dynamic estimation method of any one of the power consumption analysis tools in the above embodiments.

[0130] In one example, the electronic device may further include a communication interface 1003 and a bus 1010. The processor 1001, the memory 1002, and the communication interface 1003 are connected via the bus 1010 and communicate with each other.

[0131] The communication interface 1003 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0132] Bus 1010 includes hardware, software or both, coupling the components of the electronic device to each other. For example, but not limitation, the bus may include an accelerated graphics port (AGP) or other graphics bus, an enhanced industrial standard architecture (EISA) bus, a front-side bus (FSB), a hypertransport (HT) interconnect, an industrial standard architecture (ISA) bus, an infinite bandwidth interconnect, a low pin count (LPC) bus, a memory bus, a microchannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standard association local (VLB) bus or other suitable bus or a combination of two or more of these. Where appropriate, bus 1010 may include one or more buses. Although the present application embodiment describes and illustrates a specific bus, the present application considers any suitable bus or interconnect.

[0133] In addition, in combination with the pin capacitance dynamic estimation method in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, the pin capacitance dynamic estimation method of any power consumption analysis tool in the above embodiment is implemented.

[0134] In addition, the term "and / or" in this article is only a description of the association relationship between the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0135] It should be understood that in the embodiment of the present application, "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0136] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A pin capacitance dynamic estimation method for a power consumption analysis tool, characterized in that: The following steps are involved: Identify a starting node of a circuit, traverse the circuit downward from the starting node, and determine the first instance connected to the starting node found during the traversal as a target instance; Starting from the output pin of the target instance, traverse and search for the fan-out instance connected to the output pin of the target instance, and calculate the output pin transition time value and input pin capacitance value of the target instance; Determine whether the fan-out instance satisfies a preset traversal termination condition; if the fan-out instance does not satisfy the traversal termination condition, determine the fan-out instance as the new target instance, and return to the step of: starting from the output pin of the target instance, traverse and search for the fan-out instance connected to the output pin of the target instance, calculate the output pin transition time value and the input pin capacitance value of the target instance, until the traversal termination condition is met.

2. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 1, characterized in that: The calculating the output pin transition time value and the input pin capacitance value of the target instance includes: Calculating the output pin transition time value of the target instance based on a pin transition time lookup table, an input pin transition time value, and an output pin capacitance value, wherein the pin transition time lookup table includes a plurality of index capacitance values, index transition time values, and result transition time values ​​corresponding to the index capacitance values ​​and the index transition time values; The input pin capacitance value of the target instance is calculated based on a pin receiving capacitance lookup table, an input pin transition time value and an output pin capacitance value, wherein the pin receiving capacitance lookup table includes a plurality of index capacitance values, an index transition time value and result capacitance values ​​corresponding to the index capacitance values ​​and the index transition time value.

3. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 2, characterized in that: Before executing the calculation of the output pin transition time value and the input pin capacitance value of the target instance, it also includes: when the input pin of the target instance is connected to the starting node, the input pin transition time value of the input pin is configured as an initial transition time value preset by the user; when the input pin is connected to the output pin of other instances, the input pin transition time value is the output pin transition time value of the upper-level instance connected to the input pin.

4. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 2, characterized in that: Before executing the calculation of the output pin transition time value and the input pin capacitance value of the target instance, the method further includes: The output pin capacitance value of the target instance is configured as the input pin capacitance value of the fan-out instance connected to the output pin. When calculated for the first time, the input pin capacitance value of the fan-out instance is configured as the fixed input pin capacitance value preset for the fan-out instance in the library file.

5. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 2, characterized in that: include: In the event that there are index transition time values ​​and index capacitance values ​​that simultaneously match the input pin transition time value and the output pin capacitance value in the pin transition time lookup table or the pin receiving capacitance lookup table, the resulting transition time value that simultaneously matches the input pin transition time value and the output pin capacitance value in the pin transition time lookup table is determined as the output pin transition time value of the target instance, or, the resulting capacitance value that simultaneously matches the input pin transition time value and the output pin capacitance value in the pin receiving capacitance lookup table is determined as the input pin capacitance value of the target instance.

6. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 5, characterized in that: Also includes: In the case that there is no index transition time value that completely matches the input pin transition time value or the index capacitance value that completely matches the output pin capacitance value in the pin transition time lookup table or the pin receiving capacitance lookup table, select the two adjacent index transition time values ​​closest to the input pin transition time value or the two adjacent index capacitance values ​​closest to the output pin capacitance value, and construct a linear interpolation formula based on the result transition time value or the result capacitance value corresponding to the index transition time value or the index capacitance value in the pin transition time lookup table or the pin receiving capacitance lookup table, substitute the input pin transition time value or the output pin capacitance value into the linear interpolation formula to calculate the interpolation transition time value or the interpolation capacitance value, and determine the calculated interpolation transition time value or the interpolation capacitance value as the result transition time value or the result capacitance value.

7. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 2, characterized in that: The number of input pins of the target instance is one or more, and the number of output pins of the target instance is one or more. When the number of input pins or output pins of the target instance is multiple, the output pin transition time value or input pin capacitance value of each output pin or input pin of the target instance is calculated.

8. The pin capacitance dynamic estimation method of the power consumption analysis tool according to claim 1, characterized in that: Also includes: Determine the target number of iterations and the current number of iterations of the circuit, wherein the initial value of the current number of iterations is 0, and after the traversal termination condition is met, increment the count value of the current number of iterations by 1, and determine whether the current number of iterations is equal to the target number of iterations; if the current number of iterations is less than the target number of iterations, return to the starting node of the identified circuit, traverse the circuit downward from the starting node, and determine the first instance connected to the starting node queried during the traversal as the target instance.

9. A pin capacitance dynamic estimation device for a power consumption analysis tool, characterized in that: include: An identification module, used for identifying a starting node of a circuit, traversing the circuit downward from the starting node, and determining the first instance connected to the starting node found during the traversal as a target instance; A calculation module, used for calculating an output pin transition time value and an input pin capacitance value of the target instance; A traversal module is used to traverse along the output pin direction of the target instance to find the fan-out instance connected to the output pin, and determine whether the fan-out instance meets the preset traversal termination condition: when the fan-out instance does not meet the traversal termination condition, determine the fan-out instance as the new target instance, and return to the step of calculating the output pin transition time value and the input pin capacitance value of the target instance until the traversal termination condition is met.

10. An electronic device, characterized in that: include: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the steps of the pin capacitance dynamic estimation method of the power consumption analysis tool according to any one of claims 1 to 8 are implemented.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the steps of the pin capacitance dynamic estimation method of the power consumption analysis tool according to any one of claims 1 to 8 are implemented.

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