Thermal simulation using adaptive 3D and hierarchical grid mechanisms
A thermally aware design automation suite integrates system-level thermal awareness into design of semiconductor chips, performing fine-grain static and/or transient thermal simulations of the chips based on thermal models and boundary conditions. The thermal simulations are performed in accordance with one or more grids, with boundaries and/or resolutions being determined by adaptive and/or hierarchical multi-dimensional techniques. The adaptive grid techniques include material-boundary, rate-of-change, and convergence-information heuristics. For example, a finer grid is used in a region having higher temperature gradients compared to a region having lower temperature gradients. The hierarchical grid techniques are based on critical, intermediate, and boundary regions specified manually or automatically, each region having a respective grid resolution. For example, a critical region is analyzed according to a grid that is finer than a grid of an intermediate region, and resolution of a grid of a boundary region is adapted to boundary conditions.
1. A method comprising:
specifying a first thermal analysis region of an integrated circuit;
applying a first grid determining function to the first thermal analysis region with inputs comprising a power distribution of the integrated circuit;
applying a second grid determining function to a second thermal analysis region that extends outward from at least a portion of the first thermal analysis region; and
performing, at least in part via at least one processor, at least a portion of a thermal analysis of the integrated circuit in accordance with first and second grid resolutions respectively determined by the first and the second grid determining functions.
2. The method of claim 1 , wherein the second thermal analysis region is within the integrated circuit.
3. The method of claim 1 , wherein the at least a portion of the thermal analysis is a first portion of the thermal analysis and the applying of the first grid determining function is a first applying of the first grid determining function; and further comprising a second applying of the first grid determining function to the first thermal analysis region with inputs comprising gradients of temperatures produced by the first portion of the thermal analysis and then performing at least a second portion of the thermal analysis in accordance with a third grid resolution determined by the second applying of the first grid determining function.
4. The method of claim 1 , wherein the thermal analysis comprises computing temperatures at grid points in accordance with the first and the second grid resolutions.
5. The method of claim 1 , wherein the thermal analysis comprises computing temperature gradients with respect to grid points in accordance with the first and the second grid resolutions.
6. The method of claim 1 , wherein the first grid determining function is based on gradients of the power distribution.
7. The method of claim 1 , wherein the first thermal analysis region is a critical region, and the first grid resolution is finer than the second grid resolution.
8. The method of claim 7 , wherein a power transistor is within the critical region.
9. The method of claim 1 , wherein the specifying is manually via a user.
10. The method of claim 1 , wherein the specifying is automatically via software.
11. The method of claim 1 , wherein the specifying is based at least in part on power density.
12. A non-transitory computer-readable storage medium having a set of instructions stored therein that when executed by a processing element cause the processing element to perform operations comprising:
receiving a specification of a first thermal analysis region of an integrated circuit;
determining a first grid resolution based at least in part on power gradient thresholds of the integrated circuit;
determining a second grid resolution that is coarser than the first grid resolution; and
computing temperatures at grid points determined by applying the operation that determines the first grid resolution to the first thermal analysis region and by applying the operation that determines the second grid resolution to a second thermal analysis region that extends outward from at least a portion of the first thermal analysis region.
13. The non-transitory computer-readable storage medium of claim 12 , wherein the second thermal analysis region is within the integrated circuit.
14. The non-transitory computer-readable storage medium of claim 12 , wherein the operations further comprise iteratively using the computing temperatures operation until an error value is less than a predetermined threshold to determine temperatures of a static thermal simulation.
15. The non-transitory computer-readable storage medium of claim 12 , wherein the operations further comprise iteratively using the computing temperatures operation until an error value is less than a predetermined threshold to determine temperatures of at a particular simulation time of a transient thermal simulation.
16. The non-transitory computer-readable storage medium of claim 12 , wherein the operations further comprise determining the specification.
17. The non-transitory computer-readable storage medium of claim 12 , wherein at least one of the grid resolutions is fixed in at least one spatial dimension.
18. The non-transitory computer-readable storage medium of claim 12 , wherein at least one of the grid resolutions is variable in at least one spatial dimension.
19. The non-transitory computer-readable storage medium of claim 12 , wherein at least one of the grid resolutions is in accordance with a boundary value.
20. A non-transitory computer-readable storage medium having a set of instructions stored therein that when executed by a processing element cause the processing element to perform operations comprising:
receiving a specification of a first thermal analysis region of an integrated circuit;
determining a first grid resolution based at least in part on temperature thresholds of the integrated circuit;
determining a second grid resolution that is coarser than the first grid resolution; and
computing temperatures at grid points determined by applying the operation that determines the first grid resolution to the first thermal analysis region and by applying the operation that determines the second grid resolution to a second thermal analysis region that extends outward from at least a portion of the first thermal analysis region.
21. The non-transitory computer-readable storage medium of claim 20 , wherein the second thermal analysis region is within the integrated circuit.
22. The non-transitory computer-readable storage medium of claim 20 , wherein the operations further comprise iteratively using the computing temperatures operation until an error value is less than a predetermined threshold to determine temperatures of a static thermal simulation.
23. The non-transitory computer-readable storage medium of claim 20 , wherein the operations further comprise iteratively using the computing temperatures operation until an error value is less than a predetermined threshold to determine temperatures of at a particular simulation time of a transient thermal simulation.
24. The non-transitory computer-readable storage medium of claim 20 , wherein the operations further comprise determining the specification.
25. The non-transitory computer-readable storage medium of claim 20 , wherein at least one of the grid resolutions is fixed in at least one spatial dimension.
26. The non-transitory computer-readable storage medium of claim 20 , wherein at least one of the grid resolutions is variable in at least one spatial dimension.
27. The non-transitory computer-readable storage medium of claim 20 , wherein at least one of the grid resolutions is in accordance with a boundary value.
28. A system comprising:
a processing element; and
a memory;
wherein the memory is enabled to store instructions therein that when executed by the processing element cause the processing element to perform operations comprising:
a first grid determining operation operable at least in accordance with a power distribution of an electronic device and enabled to determine a first grid resolution,
a second grid determining operation enabled to determine a second grid resolution, the second grid resolution being coarser than the first grid resolution,
a specification receiving operation enabled to receive a specification of a first thermal analysis region of the electronic device, and
a temperature computing operation enabled to compute temperatures at grid points determined by applying the first grid determining operation to the first thermal analysis region and by applying the second grid determining operation to a second thermal analysis region that extends outward from at least a portion of the first thermal analysis region.
29. The system of claim 28 , wherein the operations further comprise an iteration control operation enabled to iteratively invoke the temperature computing operation until an error value is less than a predetermined threshold.
30. The system of claim 28 , wherein the operations further comprise a critical thermal analysis region determining operation enabled to determine the first thermal analysis region.
31. The system of claim 28 , wherein the operations further comprise a thermal simulation shell enabled to perform at least one of a static thermal simulation and a transient thermal simulation at least in part by using results of the temperature computing operation.
32. The system of claim 28 , wherein at least one of the grid resolutions is fixed in at least one spatial dimension.
33. The system of claim 28 , wherein at least one of the grid resolutions is variable in at least one spatial dimension.
34. The system of claim 28 , wherein at least one of the grid resolutions is in accordance with a boundary value.
35. A method comprising:
applying a first grid determining function to a first thermal analysis region with inputs comprising a power distribution of an integrated circuit;
deriving boundary conditions that define a second thermal analysis region of the integrated circuit;
applying a second grid determining function to the second thermal analysis region; and
performing, at least in part via at least one processor, at least a portion of a thermal analysis of the integrated circuit in accordance with first and second grid resolutions respectively determined by the first and the second grid determining functions.
36. The method of claim 35 , wherein the boundary conditions are between the first and the second regions.
37. The method of claim 35 , wherein the first region is a critical region, the second region is an intermediate region, and the boundary conditions are between the critical and the intermediate regions.
38. The method of claim 35 , wherein the deriving boundary conditions is directed to reduce total contribution to temperature rise of the first region to be less than a temperature threshold.