/asap7_reference_design

reference block design for the ASAP7nm library in Cadence Innovus

Primary LanguageVerilog

Reference Design for a modified version of ASAP7nm

This repository contains a reference block design for a modified version of the ASAP7nm library. The ASAP7nm library/PDK was developed by ASU and all credits go to them.

Here we provide a modified version of their 7nm technology. The differences are many:

  • layers M4/M5/M6/M7 are colored in the tech lef.
  • density rules are introduced, for max and min cases.

A reference design is provided as well (SHA256). The design is synthesized in Genus at 1.66GHz and it is possible to close timing on Innovus also at 1.66GHz. A reference implementation script is also provided for Cadence Innovus. The script is complete, in the sense that it provides:

  • power ring in M6-M7
  • follow pin routing in stapled style (M2-VIA-M1)
  • vertical stripes in M3
  • horizontal stripes in M4
  • signal routing in M2-M7
  • placement of tap cells
  • traditional Place->CTS->Route flow

The reference script has been evaluated on several versions of Innovus and the results are as follows:

Innovus version Floorplan DRCs Setup Hold Density
17.11 {194.04 194.04} FAIL (7) PASS (+0.020) PASS (+0.022) 70.38%
18.10 {194.04 194.04} FAIL (4) PASS (+0.023) PASS (+0.023) 70.27%
19.11 {194.04 194.04} PASS (0) PASS (+0.029) PASS (+0.021) 70.09%
20.11 {194.04 194.04} FAIL (6) PASS (+0.025) PASS (+0.020) 70.26%
21.11 {194.04 194.04} FAIL (6) PASS (+0.019) PASS (+0.019) 70.32%
- - - - - -
21.11 {183.24 183.24} FAIL (8) PASS (+0.020) PASS (+0.019) 78.91%
21.11 {172.44 172.44} FAIL (31) PASS (+0.019) PASS (+0.019) 89.07%

The designs above often fail to route due to pin access issues. All DRCs have the same "pattern" and can be fixed with some manual effort. This repository also includes two Innovus databases of the same SHA design implemented in version 19.11 and 20.11. Both databases are DRC clean. Check the folder /db/

For reference, floorplan box sizes are:

  • FP box of {0.0 0.0 172.44 172.44} means 150 std cell rows.
  • FP box of {0.0 0.0 183.24 183.24} means 160 std cell rows.
  • FP box of {0.0 0.0 194.04 194.04} means 170 std cell rows.