Unified framework and method for accurate context-aware timing modeling
A processing device determines cell boundary conditions for each of a plurality of boundaries of a cell in an integrated circuit layout and determines a layout dependent effect (LDE) impact for the cell based on the cell boundary conditions for each of the plurality of boundaries of the cell. The processing device further generates a prediction of an LDE impact on one or more contents of a library associated with the cell, and performs an LDE-aware timing analysis for the cell based on the prediction of the LDE impact on the one or more contents of the library.
1 . A method comprising:
determining, by a processing device, cell boundary conditions for each of a plurality of boundaries of a cell in an integrated circuit layout;
determining, by the processing device, layout dependent effect (LDE) impact data for the cell based on the cell boundary conditions for each of the plurality of boundaries of the cell;
generating, by the processing device, a prediction of an LDE impact on one or more contents of a library associated with the cell, wherein generating the prediction comprises converting existing composite current source (CCS) timing data from existing library data to voltage data, modifying the voltage data based on a ration of non-linear delay model (NLDM) data with the LDE impact NLDM data without the LDE impact, and converting the modified voltage data back to current data to generate predicted cell library contents that include context-aware versions of the existing library data; and
performing, by the processing device, an LDE-aware timing analysis for the cell based on the prediction of the LDE impact on the one or more contents of the library.
2 . The method of claim 1 , wherein determining the cell boundary conditions comprises identifying a presence of one or more neighboring cells at each of the plurality of boundaries of the cell in the integrated circuit layout.
3 . The method of claim 1 , wherein the LDE impact data is based on non-linear delay model (NLDM) timing data for the cell.
4 . The method of claim 1 , wherein determining the LDE impact data for the cell comprises determining respective LDE impacts based on the cell boundary conditions for each of the plurality of boundaries of the cell.
5 . The method of claim 3 , further comprising:
computing, by the processing device, a combined LDE impact for the plurality of boundaries of the cell, wherein computing the combined LDE impact comprises combining the respective LDE impacts for each of the plurality of boundaries of the cell using linear superposition.
6 . The method of claim 1 , wherein the one or more contents of the library comprise at least one of composite current source timing (CCST) data, composite current source noise (CCSN) data, or Liberty Variation Format (LVF) data, and wherein the one or more contents of the library associated with the cell do not already account for LDE impact.
7 . The method of claim 1 , wherein the cell comprises one instance of a standard cell among a plurality of cells in an integrated circuit design, and wherein the method further comprises performing an LDE-aware timing analysis for each of the plurality of cells in the integrated circuit design.
8 . A system comprising:
a memory; and
a processing device, coupled to the memory, and configured to perform operations comprising:
determining cell boundary conditions for each of a plurality of boundaries of a cell in an integrated circuit layout;
determining layout dependent effect (LDE) impact data for the cell based on the cell boundary conditions for each of the plurality of boundaries of the cell;
generating a prediction of an LDE impact on one or more contents of a library associated with the cell, wherein generating the prediction comprises converting existing composite current source (CCS) timing data from existing library data to voltage data, modifying the voltage data based on a ration of non-linear delay model (NLDM) data with the LDE impact NLDM data without the LDE impact, and converting the modified voltage data back to current data to generate predicted cell library contents that include context-aware versions of the existing library data; and
performing an LDE-aware timing analysis for the cell based on the prediction of the LDE impact on the one or more contents of the library.
9 . The system of claim 8 , wherein determining the cell boundary conditions comprises identifying a presence of one or more neighboring cells at each of the plurality of boundaries of the cell in the integrated circuit layout.
10 . The system of claim 8 , wherein the LDE impact data is based on non-linear delay model (NLDM) timing data for the cell.
11 . The system of claim 8 , wherein determining the LDE impact data for the cell comprises determining respective LDE impacts based on the cell boundary conditions for each of the plurality of boundaries of the cell.
12 . The system of claim 11 , wherein the processing device is to perform operations further comprising:
computing a combined LDE impact for the plurality of boundaries of the cell, wherein computing the combined LDE impact comprises combining the respective LDE impacts for each of the plurality of boundaries of the cell using linear superposition.
13 . The system of claim 8 , wherein the one or more contents of the library comprise at least one of composite current source timing (CCST) data, composite current source noise (CCSN) data, or Liberty Variation Format (LVF) data, and wherein the one or more contents of the library associated with the cell do not already account for LDE impact.
14 . The system of claim 8 , wherein the cell comprises one instance of a standard cell among a plurality of cells in an integrated circuit design, and wherein the method processing device is to perform operations further comprising:
performing an LDE-aware timing analysis for each of the plurality of cells in the integrated circuit design.
15 . A non-transitory computer-readable storage medium storing instructions which, when executed, cause a processing device to perform operations comprising:
determining cell boundary conditions for each of a plurality of boundaries of a cell in an integrated circuit layout;
determining layout dependent effect (LDE) impact data for the cell based on the cell boundary conditions for each of the plurality of boundaries of the cell;
generating a prediction of an LDE impact on one or more contents of a library associated with the cell, wherein generating the prediction comprises converting existing composite current source (CCS) timing data from existing library data to voltage data, modifying the voltage data based on a ration of non-linear delay model (NLDM) data with the LDE impact NLDM data without the LDE impact, and converting the modified voltage data back to current data to generate predicted cell library contents that include context-aware versions of the existing library data; and
performing an LDE-aware timing analysis for the cell based on the prediction of the LDE impact on the one or more contents of the library.
16 . The non-transitory computer-readable storage medium of claim 15 , wherein determining the cell boundary conditions comprises identifying a presence of one or more neighboring cells at each of the plurality of boundaries of the cell in the integrated circuit layout.
17 . The non-transitory computer-readable storage medium of claim 15 , wherein the LDE impact data is based on non-linear delay model (NLDM) timing data for the cell.
18 . The non-transitory computer-readable storage medium of claim 15 , wherein determining the LDE impact data for the cell comprises determining respective LDE impacts based on the cell boundary conditions for each of the plurality of boundaries of the cell.
19 . The non-transitory computer-readable storage medium of claim 18 , wherein the instructions cause the processing device to perform operations further comprising:
computing a combined LDE impact for the plurality of boundaries of the cell, wherein computing the combined LDE impact comprises combining the respective LDE impacts for each of the plurality of boundaries of the cell using linear superposition.
20 . The non-transitory computer-readable storage medium of claim 15 , wherein the one or more contents of the library comprise at least one of composite current source timing (CCST) data, composite current source noise (CCSN) data, or Liberty Variation Format (LVF) data, and wherein the one or more contents of the library associated with the cell do not already account for LDE impact.