Introduction to Virtuoso and Calibre

1
Introduction to Virtuoso and Calibre

• ?????
• ??2003.11.11

2
Outline

• Setup the environment
• Starting Cadence
• Using layout editor
• Calibre
• Conclusion

3
Environment Setup

• Copy .cdsinit and .cshrc into your main
  directory.
• 1.Source software you want.
• 2. setenv CDS_Netlisting Analog
• 3. Load Calibre.skl
• cdsinit means cadence design system
  initialization.

4
Setup .cdsinit

• Line1 setSkillPath
• (". /usr/mentor/Calibre_ss/cur/lib")
• Line2 load("calibre.skl")
• ? ??Virtuoso ?? Calibre Online Checking.
• .cshrc c shell ?????
• .cshrc ? .cdsinit???log in????????

5
Starting Cadence

• Type icfb to run Cadence in background.
• Create a New Library, as shown below

File gt New gtLibrary
6
Create a New Cell
Filegt New gtCell
Your library name
Specify your cell name
Choose Virtuso for layout view, Schematic for
schematic view
7
Create a New Cell
Filegt New gt Cell
Your library name
Specify your cell name
Choose Virtuso for layout view, Schematic for
schematic view
8
Open Layout Editor
File gt Open
Choose Library
Choose Cell
Choose Layout view
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While opening a Layout view

• Sometimes it will take a long long time to open
  it-_-
• So, please be patient

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Example Inverter
N-well
vdd
P-plus (N-IMP)
N-plus (P-IMP)
Metal 1
Poly 1
vo
vi
Diffusion
Contact
vss
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Example Inverter (Layout view)
Calibre For DRC ,LVS and PEX
LSW
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Physical Layout Techniques (1/3)

• Once a circuit design is complete, it becomes
  necessary to provide an area-efficient layout of
  the circuit to generate the masks necessary for
  fabrication.
• We must define the following NWELL, N,
  P, POLY, CONT, METAL1, DIFF, VIA1
  in the layout database for TSMC process of CIC.

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Physical Layout Techniques (2/3)
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Physical Layout Techniques (3/3)

• The n diffusion can be defined by N-plus and
  DIFF. With poly across, a NMOS is formed.
• The p diffusion can be defined by P-plus and
  DIFF. With poly across, a PMOS is formed. (PMOS
  is formed on NWELL)
• Conductor Poly and metals. They are in different
  layer and disconnected unless through CONT or
  VIA. CONT is for poly and metal1. VIA is
  used between 2 metals.
• CONT is required to connect DIFF and
  Metal1.
• After finish drawing, do not forget to place pins
  on inputs and outputs.

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LSW

• LSW Layout Select Window
• AV All visible
• NV Not visible
• AS All selectable
• NS Not selectable

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Useful Hotkeys

• Some useful hotkeys
• r draw rectangular block
• z/Z room in and room out
• k/K ruler on/off
• sstretch
• c copy

• m move
• u undo
• Del delete
• qquery
• p create path

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Option-gtDisplay
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Options-gtEditor
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Instance and Flatten Cell

• 1. Instance
• 2. Edit ? Hierarchy ? Flatten
• 3. Vdd ?Vdd, Vss?Vss , Input??Output
• 4. ??? Pin?Label

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Create Pin and Label

• ?? ??pin?material ? Metal 2
• 1. LSW ?? M2-Text
• 2. Create ? Pin
• 3. Display Pin Name ?? ??
• 4. Display Pin Option ???,?????? Material ?????
  M2_Text
• 5. ??Pin??? ,?????
• Input , output , or in/out (vdd! / Vss!)
• 6. ??ok, ???Pin??????Rectangle and (???Label ?
  Pin)

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Calibre --- DRC
Calibre gt Run DRC
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Calibre --- DRC
1.Press Rules
2.Assign your DRC rule file here
P.S. The first time you open Calibre, just choose
New Runset , which means a new setting for
rules, inputs,
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Calibre --- DRC
3.Press Inputs
4.Assign your Extracted layout file here
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Calibre --- DRC
5.Press Ouputs
6.Assign a output file name
7.Press Run DRC
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Calibre --- DRC
If you see this, it means DRC is passed
Result Window
Error listing window
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Calibre --- LVS

• Running LVS is very alike to DRC, except that we
  need not only layout, but also the extracted .sp
  file.
• So before doing LVS, please CDL out your layout
  as .sp

1.Specify Rule file 2.Assign Layout file and
Netlist file 3.Check the output file and debug
if necessary
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Conclusion

• Calibre is pretty friendly(at least its more
  convenient than Dracula)
• As you can see, Calibre is a GUI software,
  helping you to check DRC and LVS
• However, if you want to be good at it, please
  take time and practice it patiently
• I will put DRC, LVS and LPE rule files at our
  course web, if we will need it for HW3.

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• Thank you for your attention !