Circuit timing long-term reliability analysis system and method integrating temperature distribution

Abstract

A circuit long-term reliability timing analysis system integrating temperature distribution includes: a circuit logic simulation module, a component position information acquisition module, a temperature distribution estimation module, a transistor threshold voltage calculation module, a circuit timing analysis module, a circuit analysis condition refresh module and a cycle control module. The present invention realizes a relatively comprehensive discovery of circuit design reliability problems by performing timing analysis within the circuit design life cycle through a circuit timing long-term reliability analysis system integrating temperature distribution and a method, while taking into account the influence of temperature on the aging of each component.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit timing long-term reliability analysis, and in particular to a circuit timing long-term reliability analysis system and method integrating temperature distribution. Background Art

[0002] Existing circuit long-term reliability simulation technologies include Figure 1 As shown, firstly, a transient simulation is performed on the new circuit to initialize the device stress and simulation times in the circuit; then, a reliability (aging) simulation is implemented through a predetermined number of transient simulations. In each iteration, the pressure accumulation of each device in the simulation process (i.e., the working process) in the previous circuit simulation is first calculated, and then the historical pressure sum of the device is updated according to the pressure accumulation of the previous simulation. Further, the parameter threshold voltage and mobility are updated according to the historical pressure sum of the device, and the updated parameters are applied to this circuit transient simulation.

[0003] The transient simulation process is relatively time-consuming. At the same time, the scale of digital circuits is large, especially digital systems on chip (SoC). The long-term reliability simulation of circuits based on transient simulation is difficult to apply to large-scale digital circuits or digital SoCs or mixed-signal SoCs.

[0004] In addition, the existing technology does not consider the impact of temperature distribution on the long-term reliability of the circuit, especially when the circuit operates in a high temperature environment, or when the power consumption of different parts of the chip varies greatly, resulting in large differences in temperature distribution on the chip. It is inaccurate not to consider the impact of temperature on the long-term reliability of the circuit or to use a uniform temperature to consider the impact of the long-term reliability of the circuit, which will lead to the omission of possible reliability problems in the design stage.

[0005] The existing circuit timing analysis is an effective way to check the timing problems in the circuit design, and can find the timing problems in the design faster than through the circuit transient simulation and logic simulation. The circuit unit characterization data used in the existing timing analysis is fixed and does not change with the circuit working time. It fails to consider the impact of the performance degradation caused by device aging (device threshold voltage change and carrier mobility reduction in the device) on the circuit timing during the circuit design life. For integrated circuits with a short design life, this approximate timing analysis method is acceptable, because in a short working period, the characteristic data of the circuit unit changes very little and can be ignored. For integrated circuits with a very long design life, the change of device threshold voltage and device carrier mobility is more obvious. In the timing analysis, it is necessary to consider the impact of the change of device threshold voltage and device carrier mobility on the timing correctness. The results of relying on traditional circuit timing analysis are very different from the timing shown in actual work, and may even be wrong. In addition, in the existing timing analysis technology, all parts of the entire integrated circuit chip are analyzed at the same temperature, but the actual situation is that the temperature of each part of the circuit is different. During the long-term operation of the circuit, the temperature has a more obvious impact on the aging of the device. Therefore, during the design life of the circuit, the aging degree of the devices in various places is also different. In order to more comprehensively discover the reliability problems of the circuit design, it is necessary to perform timing analysis during the design life of the circuit, and the timing analysis needs to consider the impact of temperature on the aging of each device. Summary of the invention

[0006] In view of this, the main purpose of the present invention is to provide a circuit timing long-term reliability analysis system and method integrating temperature distribution, in order to at least partially solve at least one of the above-mentioned technical problems.

[0007] In order to achieve the above object, as one aspect of the present invention, a circuit timing long-term reliability analysis system integrating temperature distribution is provided, comprising:

[0008] The circuit logic simulation module performs logic simulation on the circuit according to the initial threshold voltage and initial simulation temperature, or the threshold voltage and current operating temperature of each transistor after being refreshed by the circuit analysis condition refresh module, and transmits the logic simulation result to the temperature distribution estimation module and the transistor threshold voltage calculation module;

[0009] A component position information acquisition module, used to acquire the component position information of the circuit and transmit the component position information to the temperature distribution estimation module;

[0010] A temperature distribution estimation module estimates the temperature distribution of the circuit according to the circuit logic simulation results obtained by the circuit logic simulation module and the position information of the components of the circuit, and transmits it to the circuit timing analysis module, the circuit analysis condition refresh module and the transistor threshold voltage calculation module;

[0011] A transistor threshold voltage calculation module calculates the new threshold voltage of each transistor according to the circuit logic simulation result obtained by the circuit logic simulation module and the temperature distribution of the circuit, and transmits it to the circuit timing analysis module and the circuit analysis condition refresh module;

[0012] A circuit timing analysis module performs timing analysis on the circuit according to the current threshold voltage of each transistor obtained by the transistor threshold voltage calculation module and the current operating temperature obtained by the temperature distribution estimation module, and transmits the timing analysis result to the loop control module;

[0013] A circuit analysis condition refresh module refreshes the threshold voltage and operating temperature of each transistor according to the operating temperature obtained by the temperature distribution estimation module and the transistor threshold voltage obtained by the transistor threshold voltage calculation module;

[0014] The loop control module is used to repeatedly execute the above process until a predetermined number of analyses is reached.

[0015] The component position information acquisition module acquires the component position information of the circuit from the physical layout data of the circuit, or estimates the component position information in the circuit based on the physical virtual prototype technology.

[0016] Wherein, the temperature distribution estimation module includes:

[0017] The power consumption estimation submodule calculates the power consumption of each component and connection in the circuit according to the circuit logic simulation results;

[0018] The heat source setting submodule sets the heat source in the chip based on the average power consumption of each component and connection in the circuit and the component location information;

[0019] Thermal analysis submodule, which performs three-dimensional thermal analysis on the chip to obtain thermal distribution data;

[0020] The component temperature acquisition submodule acquires the temperature at the location of each component based on the heat distribution data obtained by three-dimensional thermal analysis and the location of the components.

[0021] Wherein, the circuit long-term reliability timing analysis system also includes:

[0022] The circuit temperature distribution prediction module performs model fitting on the circuit temperature distribution obtained by estimating the circuit temperature distribution corresponding to each simulation according to the several logic simulations of the logic simulation module and the circuit temperature distribution estimation module, and directly calculates the circuit temperature distribution after several future logic simulations with this model;

[0023] The transistor threshold voltage prediction module performs model fitting on the transistor threshold voltage values ​​obtained by calculating the transistor threshold voltages corresponding to each simulation according to several logic simulations of the logic simulation module and the transistor threshold voltage calculation module, and uses this model to directly calculate the transistor threshold voltage values ​​after several future logic simulations.

[0024] The actual simulation and model prediction gating control module controls the gating logic simulation module, the circuit temperature distribution estimation module, the transistor threshold voltage calculation module, or the gating circuit temperature distribution prediction module and the transistor threshold voltage prediction module.

[0025] Preferably, the actual simulation and model prediction gating control module comprises:

[0026] A first counter submodule counts the number of times the logic simulation module, the circuit temperature distribution estimation module, and the transistor threshold voltage calculation module are continuously selected;

[0027] A second counter submodule counts the number of times the circuit temperature distribution prediction module and the transistor threshold voltage prediction module are continuously selected to replace the logic simulation module, the circuit temperature distribution estimation module, and the transistor threshold voltage calculation module;

[0028] A first counting comparison submodule, which compares the count value of the first counter with a first specified number of times, and when the count value of the first counter is equal to the first specified number of times, the circuit temperature distribution prediction module and the transistor threshold voltage prediction module are gated;

[0029] The second counting comparison submodule compares the count value of the second counter with the second specified number of times. When the count value of the second counter is equal to the second specified number of times, the second counter is reset, and the logic simulation module, the circuit temperature distribution estimation module, and the transistor threshold voltage calculation module are selected.

[0030] As another aspect of the present invention, a circuit timing long-term reliability analysis method integrating temperature distribution is provided, comprising the following steps:

[0031] Set the initial operating temperature of each device;

[0032] Perform logic simulation on the circuit according to the current threshold voltage and operating temperature of each transistor;

[0033] Estimate the temperature distribution of the circuit based on the circuit logic simulation results combined with the circuit component location information;

[0034] Calculate the new threshold voltage of each transistor based on the logic simulation results of the circuit and the temperature distribution of the circuit;

[0035] Refresh the threshold voltage and operating temperature of each transistor;

[0036] Determine the threshold voltage and operating temperature corresponding to each device in circuit timing analysis;

[0037] Performing timing analysis on the circuit according to the determined threshold voltage and operating temperature of each transistor;

[0038] Repeat the above process until the predetermined number of analyses is reached or a long-term reliability problem of the circuit timing is found;

[0039] Preferably, the position information of the components of the circuit can be obtained from the physical layout data of the circuit, or the position information of the components in the circuit can be estimated based on the physical virtual prototype technology.

[0040] The method of estimating the temperature distribution of the circuit according to the circuit logic simulation result combined with the position information of the components of the circuit comprises the following sub-steps:

[0041] Calculate the power consumption of each component and connection in the circuit according to the circuit logic simulation results;

[0042] The heat source is set in the chip based on the average power consumption of each component and connection in the circuit and the component position information;

[0043] Conduct three-dimensional thermal analysis on the chip to obtain thermal distribution data;

[0044] The temperature at the location of each component is obtained based on the heat distribution data obtained by three-dimensional thermal analysis and the location information of the components.

[0045] The step of calculating the new threshold voltage of each transistor according to the logic simulation result of the circuit combined with the temperature distribution of the circuit includes the following sub-steps:

[0046] Calculate the effective stress time of each device in the circuit according to the logic simulation results of the circuit;

[0047] Calculate the threshold voltage drift of the device due to gate bias temperature instability (BTI) effect based on the effective stress time of the device;

[0048] Calculate the threshold voltage drift due to hot carrier injection (HCI) effect based on the temperature of the device location and the simulation time length;

[0049] The total drift amount is calculated according to the drift amount of the threshold voltage due to the BTI effect and the drift amount due to the HCI effect, thereby obtaining a new threshold voltage.

[0050] Among them, in the step of determining the threshold voltage and operating temperature corresponding to each device in the circuit timing analysis:

[0051] Set the threshold voltage and operating temperature of each device to the initial threshold voltage and operating temperature of each device in this timing analysis, or

[0052] Set the threshold voltage and operating temperature of each device to the threshold voltage and operating temperature of each device determined after logic simulation before this timing analysis, or

[0053] The threshold voltage and operating temperature corresponding to each device are set to the intermediate value determined according to the threshold voltage and operating temperature of each device determined before the logic simulation before this timing analysis and the threshold voltage and operating temperature of each device determined after the logic simulation before this timing analysis.

[0054] The performing of timing analysis on the circuit according to the determined threshold voltage and operating temperature of each transistor is to obtain corresponding characterization data for timing analysis according to the threshold voltage and operating temperature of each transistor in the circuit unit entity.

[0055] The circuit long-term reliability timing analysis method further comprises the following steps:

[0056] Predict circuit temperature distribution, and fit the circuit temperature distribution model obtained by estimating the circuit temperature distribution corresponding to several logic simulations and each simulation, and use this model to directly calculate the circuit temperature distribution after several future logic simulations;

[0057] Predict transistor threshold voltages, perform model fitting based on several logic simulations and the transistor threshold voltages corresponding to each simulation, and use this model to directly calculate transistor threshold voltages after several future logic simulations;

[0058] Preferably, the logic simulation, circuit temperature distribution estimation, transistor threshold voltage calculation and circuit temperature distribution prediction, transistor threshold voltage prediction can be alternately controlled by actual simulation and model prediction gating mechanism, and the mechanism includes the following steps:

[0059] The long-term reliability analysis of the circuit for the initial first specified number of times uses logic simulation, circuit temperature distribution estimation, and transistor threshold voltage calculation;

[0060] After the initial first specified number of times, logic simulation, circuit temperature distribution estimation, transistor threshold voltage calculation and circuit temperature distribution prediction, transistor threshold voltage prediction can be performed alternately;

[0061] The number of consecutive uses of circuit temperature distribution prediction and transistor threshold voltage prediction does not exceed a second specified number of times.

[0062] Based on the above technical solution, it can be known that the circuit timing long-term reliability analysis system and method integrating temperature distribution of the present invention has at least some of the following beneficial effects compared with the prior art:

[0063] (1) The present invention integrates the circuit timing long-term reliability analysis system and method with temperature distribution to perform timing analysis within the circuit design life cycle, thereby achieving a relatively comprehensive discovery of circuit design reliability issues while taking into account the impact of temperature on the aging of each component.

[0064] (2) The present invention reduces the number of logic simulations and the corresponding temperature distribution estimation and transistor threshold voltage value estimation as well as the number of circuit timing analysis by predicting circuit temperature distribution and transistor threshold voltage, thereby speeding up the circuit timing long-term reliability analysis speed.

[0065] (3) The present invention can improve the speed while ensuring the accuracy of long-term timing reliability analysis by alternating logic simulation, circuit temperature distribution estimation, transistor threshold voltage calculation and circuit temperature distribution prediction and transistor threshold voltage prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a flow chart of circuit long-term reliability simulation technology in the prior art;

[0067] Figure 2 It is a schematic diagram of each module of the circuit timing long-term reliability analysis system integrating temperature distribution of the present invention;

[0068] Figure 3 It is a flow chart of the circuit timing long-term reliability analysis method integrating temperature distribution of the present invention. DETAILED DESCRIPTION

[0069] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0070] like Figure 2 As shown, a circuit long-term reliability timing analysis system integrating temperature distribution includes:

[0071] A circuit logic simulation module performs logic simulation on the circuit according to the current threshold voltage of each transistor obtained by the transistor threshold voltage calculation module and the current operating temperature obtained by the temperature distribution estimation module;

[0072] A circuit timing analysis module performs timing analysis on the circuit according to the current threshold voltage of each transistor obtained by the transistor threshold voltage calculation module and the current operating temperature obtained by the temperature distribution estimation module;

[0073] A component position information acquisition module, used to acquire the component position information of the circuit;

[0074] A temperature distribution estimation module estimates the temperature distribution of the circuit according to the circuit logic simulation results obtained by the circuit logic simulation module and the position information of the components of the circuit;

[0075] A transistor threshold voltage calculation module calculates a new threshold voltage of each transistor based on the circuit logic simulation result obtained by the circuit logic simulation module and the temperature distribution of the circuit;

[0076] A circuit analysis condition refresh module refreshes the threshold voltage and operating temperature of each transistor according to the operating temperature obtained by the temperature distribution estimation module and the transistor threshold voltage obtained by the transistor threshold voltage calculation module;

[0077] The loop control module is used to repeat the above process until a predetermined number of analyses is reached.

[0078] In the above-mentioned circuit long-term reliability timing analysis system, the component position information acquisition module acquires the circuit component position information from the circuit physical layout data, or estimates the position information of the components in the circuit based on the physical virtual prototype technology.

[0079] Wherein, the temperature distribution estimation module includes:

[0080] The power consumption estimation submodule calculates the power consumption of each component and connection in the circuit according to the circuit logic simulation results;

[0081] The heat source setting submodule sets the heat source in the chip based on the average power consumption of each component and connection in the circuit and the component location information;

[0082] Thermal analysis submodule performs three-dimensional thermal analysis on the chip to obtain stable thermal distribution data;

[0083] The component temperature acquisition submodule acquires the temperature of each component location based on the stable heat distribution data obtained by three-dimensional thermal analysis and the location of the components.

[0084] Wherein, the circuit long-term reliability timing analysis system also includes:

[0085] The circuit temperature distribution prediction module performs model fitting on the circuit temperature distribution obtained by estimating the circuit temperature distribution corresponding to each simulation according to the several logic simulations of the logic simulation module and the circuit temperature distribution estimation module, and directly calculates the circuit temperature distribution after several future logic simulations with this model;

[0086] The transistor threshold voltage prediction module performs model fitting on the transistor threshold voltage values ​​obtained by calculating the transistor threshold voltages corresponding to each simulation according to several logic simulations of the logic simulation module and the transistor threshold voltage calculation module, and uses this model to directly calculate the transistor threshold voltage values ​​after several future logic simulations.

[0087] The actual simulation and model prediction module controls the gating logic simulation module, the circuit temperature distribution estimation module, the transistor threshold voltage calculation module, or the gating circuit temperature distribution prediction module and the transistor threshold voltage prediction module.

[0088] The actual simulation and model prediction gating control module includes:

[0089] A first counter submodule counts the number of times the logic simulation module, the circuit temperature distribution estimation module, and the transistor threshold voltage calculation module are continuously selected;

[0090] A second counter submodule counts the number of times the circuit temperature distribution prediction module and the transistor threshold voltage prediction module are continuously selected to replace the logic simulation module, the circuit temperature distribution estimation module, and the transistor threshold voltage calculation module;

[0091] A first counting comparison submodule, which compares the count value of the first counter with a first specified number of times, and when the count value of the first counter is equal to the first specified number of times, the circuit temperature distribution prediction module and the transistor threshold voltage prediction module are gated;

[0092] The second counting comparison submodule compares the count value of the second counter with the second specified number of times. When the count value of the second counter is equal to the second specified number of times, the second counter is reset, and the logic simulation module, the circuit temperature distribution estimation module, and the transistor threshold voltage calculation module are selected.

[0093] like Figure 3 As shown, this embodiment also discloses a circuit long-term reliability timing analysis method using the circuit long-term reliability timing analysis system as described above, comprising the following steps:

[0094] Set the initial operating temperature of each device;

[0095] Perform logic simulation on the circuit according to the current threshold voltage and operating temperature of each transistor;

[0096] Estimate the temperature distribution of the circuit based on the circuit logic simulation results combined with the circuit component location information;

[0097] Calculate the new threshold voltage of each transistor based on the logic simulation results of the circuit and the temperature distribution of the circuit;

[0098] Refresh the threshold voltage and operating temperature of each transistor;

[0099] Determine the threshold voltage and operating temperature corresponding to each device in circuit timing analysis;

[0100] Performing timing analysis on the circuit according to the determined threshold voltage and operating temperature of each transistor;

[0101] Repeat the above process until the predetermined number of analyses is reached or a long-term reliability problem of the circuit timing is found;

[0102] The position information of the components of the circuit can be obtained from the physical layout data of the circuit, or the position information of the components in the circuit can be estimated based on the physical virtual prototype technology.

[0103] In the above-mentioned circuit long-term reliability timing analysis method, the estimating of the temperature distribution of the circuit according to the circuit logic simulation result combined with the circuit component position information includes the following sub-steps:

[0104] Calculate the power consumption of each component and connection in the circuit according to the circuit logic simulation results;

[0105] The heat source is set in the chip based on the average power consumption of each component and connection in the circuit and the component position information;

[0106] Conduct three-dimensional thermal analysis on the chip to obtain stable thermal distribution data;

[0107] The temperature at the location of each component is obtained based on the stable heat distribution data obtained by three-dimensional thermal analysis and the position information of the components.

[0108] The step of calculating the new threshold voltage of each transistor according to the logic simulation result of the circuit combined with the temperature distribution of the circuit includes the following sub-steps:

[0109] Calculate the effective stress time of each device in the circuit according to the logic simulation results of the circuit;

[0110] Calculate the threshold voltage drift of the device due to the BTI effect based on the effective stress time of the device;

[0111] Calculate the threshold voltage drift due to the HCI effect based on the temperature at the device location and the simulation time length;

[0112] The total drift amount is calculated according to the drift amount of the threshold voltage due to the BTI effect and the drift amount due to the HCI effect, thereby obtaining a new threshold voltage.

[0113] Among them, in the step of determining the threshold voltage and operating temperature corresponding to each device in the circuit timing analysis:

[0114] Set the threshold voltage and operating temperature of each device to the initial threshold voltage and operating temperature of each device in this timing analysis, or

[0115] Setting the threshold voltage and operating temperature corresponding to each device to the threshold voltage and operating temperature of each device determined after logic simulation before this timing analysis, or;

[0116] The threshold voltage and operating temperature corresponding to each device are set to the intermediate value determined by the threshold voltage and operating temperature of each device determined after the logic simulation before this timing analysis and the threshold voltage and operating temperature of each device determined after the logic simulation before this timing analysis.

[0117] In this embodiment, the performing of timing analysis on the circuit according to the determined threshold voltage and operating temperature of each transistor is to obtain corresponding characterization data for timing analysis according to the threshold voltage and operating temperature of each transistor in the circuit unit entity.

[0118] The above circuit long-term reliability timing analysis method also includes the following steps:

[0119] Predict circuit temperature distribution, and fit the circuit temperature distribution model obtained by estimating the circuit temperature distribution corresponding to several logic simulations and each simulation, and use this model to directly calculate the circuit temperature distribution after several future logic simulations;

[0120] Predict transistor threshold voltages, perform model fitting based on several logic simulations and the transistor threshold voltages corresponding to each simulation, and use this model to directly calculate transistor threshold voltages after several future logic simulations;

[0121] This reduces the number of logic simulations and the corresponding temperature distribution estimation, transistor threshold voltage estimation, and circuit timing analysis, thereby speeding up the long-term reliability analysis of circuit timing.

[0122] The logic simulation, circuit temperature distribution estimation, transistor threshold voltage calculation and circuit temperature distribution prediction, transistor threshold voltage prediction can be performed alternately to improve the speed while ensuring the accuracy of long-term timing reliability analysis.

[0123] The logic simulation, circuit temperature distribution estimation, transistor threshold voltage calculation and circuit temperature distribution prediction, transistor threshold voltage prediction can be performed alternately under the control of actual simulation and model prediction gating mechanism:

[0124] The long-term reliability analysis of the circuit for the initial first specified number of times uses logic simulation, circuit temperature distribution estimation, and transistor threshold voltage calculation;

[0125] After the initial first specified number of times, logic simulation, circuit temperature distribution estimation, transistor threshold voltage calculation and circuit temperature distribution prediction, transistor threshold voltage prediction can be performed alternately;

[0126] The number of consecutive uses of circuit temperature distribution prediction and transistor threshold voltage prediction does not exceed a second specified number of times.

[0127] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A circuit long-term reliability timing analysis system integrating temperature distribution, characterized in that: include: The circuit logic simulation module performs logic simulation on the circuit according to the initial threshold voltage and initial simulation temperature, or the threshold voltage and current operating temperature of each transistor after being refreshed by the circuit analysis condition refresh module, and transmits the logic simulation result to the temperature distribution estimation module and the transistor threshold voltage calculation module; A component position information acquisition module, used to acquire the component position information of the circuit and transmit the component position information to the temperature distribution estimation module; A temperature distribution estimation module estimates the temperature distribution of the circuit according to the circuit logic simulation result obtained by the circuit logic simulation module in combination with the component position information of the circuit, and transmits the current operating temperature obtained by the temperature distribution estimation module to the circuit timing analysis module, the circuit analysis condition refresh module and the transistor threshold voltage calculation module; A transistor threshold voltage calculation module, which calculates a new threshold voltage of each transistor according to the logic simulation result of the circuit obtained by the circuit logic simulation module in combination with the temperature distribution of the circuit, and transmits the current threshold voltage of each transistor obtained by the transistor threshold voltage calculation module to the circuit timing analysis module and the circuit analysis condition refresh module; A circuit timing analysis module, which performs a timing analysis on the circuit according to the threshold voltage of each transistor currently obtained by the transistor threshold voltage calculation module and the current operating temperature obtained by the temperature distribution estimation module, and transmits the timing analysis result to the cycle control module; A circuit analysis condition refreshing module, which refreshes the threshold voltage and operating temperature of each transistor according to the operating temperature obtained by the temperature distribution estimating module and the transistor threshold voltage obtained by the transistor threshold voltage calculating module; The loop control module is used to repeatedly execute the process of performing timing analysis on the circuit until a predetermined number of analysis times is reached.

2. The circuit long-term reliability timing analysis system according to claim 1, characterized in that: The component position information acquisition module acquires the component position information of the circuit from the physical layout data of the circuit, or estimates the component position information in the circuit based on the physical virtual prototype technology.

3. The circuit long-term reliability timing analysis system according to claim 1, characterized in that: The temperature distribution estimation module comprises: A power consumption estimation submodule calculates the power consumption of each component and connection in the circuit according to the circuit logic simulation result; A heat source setting submodule is used to set a heat source in the chip based on the average power consumption of each component and connection in the circuit and the position information of the component; A thermal analysis submodule performs three-dimensional thermal analysis on the chip to obtain thermal distribution data; The component temperature acquisition submodule acquires the temperature of each component at its location according to the heat distribution data obtained by the three-dimensional thermal analysis and the location of the component.

4. The circuit long-term reliability timing analysis system according to claim 1, characterized in that: The circuit long-term reliability timing analysis system also includes: A circuit temperature distribution prediction module performs model fitting on the circuit temperature distribution obtained by estimating the circuit temperature distribution corresponding to each simulation according to the several logic simulations of the circuit logic simulation module and the temperature distribution estimation module, and directly calculates the circuit temperature distribution after several future logic simulations using this model; A transistor threshold voltage prediction module performs model fitting on the threshold voltage value of the transistor obtained by calculating the transistor threshold voltage corresponding to each simulation according to several logic simulations of the circuit logic simulation module and the transistor threshold voltage calculation module, and directly calculates the threshold voltage value of the transistor after several future logic simulations using this model; An actual simulation and model prediction gating control module controls whether to gating the circuit logic simulation module, the temperature distribution estimation module, the transistor threshold voltage calculation module, or the circuit temperature distribution prediction module and the transistor threshold voltage prediction module; Wherein, the actual simulation and model prediction gating control module includes: A first counter submodule, which counts the number of times the circuit logic simulation module, the temperature distribution estimation module, and the transistor threshold voltage calculation module are continuously turned on; A second counter submodule counts the number of times the circuit temperature distribution prediction module and the transistor threshold voltage prediction module are continuously selected to replace the circuit logic simulation module, the temperature distribution estimation module, and the transistor threshold voltage calculation module; a first counting comparison submodule, which compares the count value of the first counter with a first specified number of times, and when the count value of the first counter is equal to the first specified number of times, enables the circuit temperature distribution prediction module and the transistor threshold voltage prediction module; The second counting comparison submodule compares the count value of the second counter with the second specified number of times. When the count value of the second counter is equal to the second specified number of times, the second counter is reset, and the circuit logic simulation module, the temperature distribution estimation module, and the transistor threshold voltage calculation module are enabled.

5. A circuit long-term reliability timing analysis method using the circuit long-term reliability timing analysis system according to any one of claims 1 to 4, characterized in that: The following steps are involved: Set the initial operating temperature of each device; Perform logic simulation on the circuit according to the current threshold voltage and operating temperature of each transistor; Estimate the temperature distribution of the circuit based on the circuit logic simulation results combined with the circuit component location information; Calculate the new threshold voltage of each transistor according to the circuit logic simulation result combined with the temperature distribution of the circuit; Refresh the threshold voltage and operating temperature of each transistor; Determine the threshold voltage and operating temperature corresponding to each device in circuit timing analysis; Performing timing analysis on the circuit according to the determined threshold voltage and operating temperature of each transistor; Repeat the above process until the predetermined number of analyses is reached or a long-term reliability problem of the circuit timing is found; The position information of the components of the circuit can be obtained from the physical layout data of the circuit, or the position information of the components in the circuit can be estimated based on the physical virtual prototype technology.

6. The circuit long-term reliability timing analysis method according to claim 5, characterized in that: The method of estimating the temperature distribution of the circuit according to the circuit logic simulation result combined with the position information of the components of the circuit comprises the following sub-steps: Calculate the power consumption of each component and connection in the circuit according to the circuit logic simulation result; Setting a heat source in the chip based on the average power consumption of each component and connection in the circuit and the position information of the component; Performing three-dimensional thermal analysis on the chip to obtain thermal distribution data; The temperature at the location of each component is obtained based on the heat distribution data obtained by three-dimensional thermal analysis and the position information of the components.

7. The circuit long-term reliability timing analysis method according to claim 5, characterized in that: The step of calculating the new threshold voltage of each transistor according to the logic simulation result of the circuit combined with the temperature distribution of the circuit includes the following sub-steps: Calculate the effective stress time of each device in the circuit according to the circuit logic simulation result; Calculating the drift of the threshold voltage of the device due to the gate bias temperature instability effect according to the effective stress time of the device; Calculate the threshold voltage drift due to hot carrier injection effect based on the temperature of the device location and the simulation time length; The total drift amount is calculated according to the drift amount of the threshold voltage due to the gate bias temperature instability effect and the drift amount due to the hot carrier injection effect, so as to obtain a new threshold voltage.

8. The circuit long-term reliability timing analysis method according to claim 5, characterized in that: In the step of determining the threshold voltage and operating temperature corresponding to each device in the circuit timing analysis: Set the threshold voltage and operating temperature corresponding to each device as the initial threshold voltage and operating temperature corresponding to each device in this timing analysis, or The threshold voltage and operating temperature corresponding to each device are set to the threshold voltage and operating temperature of each device determined after the logic simulation before the timing analysis, or The threshold voltage and operating temperature corresponding to each device are set to an intermediate value determined according to the threshold voltage and operating temperature of each device determined before the logic simulation before the current timing analysis and the threshold voltage and operating temperature of each device determined after the logic simulation before the current timing analysis.

9. The circuit long-term reliability timing analysis method according to claim 5, characterized in that: The performing of timing analysis on the circuit according to the determined threshold voltages and operating temperatures of each transistor is to obtain corresponding characterization data for timing analysis according to the threshold voltages and operating temperatures of each transistor in the circuit unit entity.

10. The circuit long-term reliability timing analysis method according to claim 5, characterized in that: The circuit long-term reliability timing analysis method also includes the following steps: Predict circuit temperature distribution, and fit the circuit temperature distribution model obtained by estimating the circuit temperature distribution corresponding to several logic simulations and each simulation, and use this model to directly calculate the circuit temperature distribution after several future logic simulations; Predicting the transistor threshold voltage, performing model fitting based on the threshold voltage values ​​of the transistors calculated according to the several logic simulations and the transistor threshold voltages corresponding to each simulation, and directly calculating the transistor threshold voltage values ​​after several future logic simulations using this model; The logic simulation, the circuit temperature distribution estimation, the transistor threshold voltage calculation, the circuit temperature distribution prediction, and the transistor threshold voltage prediction can be alternately controlled by the actual simulation and model prediction gating mechanism, and the mechanism includes the following steps: The long-term reliability analysis of the circuit for the first specified number of times initially adopts the logic simulation, the circuit temperature distribution estimation, and the transistor threshold voltage calculation; After the initial first specified number of times, the logic simulation, the circuit temperature distribution estimation, the transistor threshold voltage calculation and the circuit temperature distribution prediction, the transistor threshold voltage prediction can be performed alternately; The number of times the circuit temperature distribution prediction and the transistor threshold voltage prediction are continuously adopted does not exceed a second specified number of times.

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