 Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use different cell from library

TOOL FLOWFUNCTION  Uses Perl to open path and write celllist.lst  Skill and Perl work together to generate schematic with all cells  Start Cadence and collect info with log file

TOOL FLOWFUNCTION  Skill Creates secondary library of cells for testing  Big ocean created with Perl which contains test information for each cell  Ocean runs and creates individual results  Perl script checks outputs

The figure below displays a typical testing setup for a cell from the ST 120 library. Another thought to keep in mind is the timing of the waveforms of the inputs.

Want a process TT (typical N&P) to sit on the balanced process line These effects are amplified due to the exponential dependence on current in sub- threshold SF corner is a worst case scenario in P-Strong (left box) FS corner is the worst case scenario in N-Strong (right box)

ST MICRO 90 (715 CELLS) Includes D FF’s & D latches Tested at Tmin = 2 uSec Vdd FF TT SS FS SF ST MICRO 120 (698 CELLS) Includes D FF’s & D latches Tested at Tmin = 2 uSec Vdd FF TT SS FS SF

ST MICRO 90 (715 CELLS) Not Including D FF’s & D latches Tested at Tmin = 2 uSec Vdd FF TT SS FS SF ST MICRO 120 (698 CELLS) Not Including D FF’s & D latches Tested at Tmin = 2 uSec Vdd FF TT SS FS SF