Save power Scale down power rail Ensure Reliability Issues with variation Issues with timing ...

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Transcript of Save power Scale down power rail Ensure Reliability Issues with variation Issues with timing ...

Page 1: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.
Page 2: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

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

Page 3: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

TOOL FLOW FUNCTION

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

Page 4: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

TOOL FLOW FUNCTION

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

Page 5: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

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.

Page 6: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

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)

Page 7: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

ST MICRO 90 (715 CELLS)

Includes D FF’s & D latches

Tested at Tmin = 2 uSec

Vdd FF TT SS FS SF .35 20 20 18 15 24 .3 17 21 21 15 35.25 20 20 20 15 49 .2 22 19 21 13 57

ST MICRO 120 (698 CELLS)

Includes D FF’s & D latches

Tested at Tmin = 2 uSec

Vdd FF TT SS FS SF .35 22 25 29 10 35 .3 25 25 28 8 41 .25 25 27 27 8 41 .2 25 29 29 8 41

Page 8: Save power  Scale down power rail  Ensure Reliability  Issues with variation  Issues with timing  Identify and Replace  Use custom cell  Use.

ST MICRO 90 (715 CELLS)

Not Including D FF’s & D latches

Tested at Tmin = 2 uSec

Vdd FF TT SS FS SF .35 4 4 4 4 5.3 4 4 4 4 5.25 4 4 4 4 5.2 4 4 4 4 5

ST MICRO 120 (698 CELLS)

Not Including D FF’s & D latches

Tested at Tmin = 2 uSec

Vdd FF TT SS FS SF .35 5 5 5 5 5 .3 5 5 5 5 5 .25 5 5 5 5 5.2 5 5 13 8 5