Download - EE 201A/EE298 Modeling and Optimization for VLSI Layout Instructor: Lei He Email: [email protected]
Outline
Course logisticsCourse logistics
OverviewOverview What are covered in the courseWhat are covered in the course What are interesting trends for physical designWhat are interesting trends for physical design
Instructor Info
Email: [email protected]: [email protected] Phone: 310-206-2037Phone: 310-206-2037 Office: Engineering IV 68-117Office: Engineering IV 68-117 Office hours: Tu/Th 2-3pm or by Office hours: Tu/Th 2-3pm or by
appointmentappointment The best way to reach me: The best way to reach me:
Email with EE201 in subject lineEmail with EE201 in subject line
About this Course
One of selective course for EE’s ECS Major Field StudentsOne of selective course for EE’s ECS Major Field Students Question in M.S. comprehensive exam / PhD prelimsQuestion in M.S. comprehensive exam / PhD prelims Offered every other springOffered every other spring Will be under another course number (EE205B)Will be under another course number (EE205B)
Related coursesRelated courses Mani’s EE202A Embedded Computing Systems (Fall)Mani’s EE202A Embedded Computing Systems (Fall) Ingrid’s EE201A on Advanced VLSI (Spring)Ingrid’s EE201A on Advanced VLSI (Spring) Bill M-S’s EE204A on Compilers (Winter)Bill M-S’s EE204A on Compilers (Winter) My EE205A Fundamental to CAD (Winter)My EE205A Fundamental to CAD (Winter)
Mani’s EE206A Wireless Systems (Spring)Mani’s EE206A Wireless Systems (Spring) My EE205B (every other Spring)My EE205B (every other Spring)
Course Prerequisites
Official prerequisiteOfficial prerequisite EE116BEE116B VLSI System DesignVLSI System Design But mainly self-containedBut mainly self-contained
Knowledge to help you appreciate moreKnowledge to help you appreciate more CS180CS180 Introduction to algorithmsIntroduction to algorithms
EE205A and EE205B EE205A Fundamental to CAD of embedded systemsEE205A Fundamental to CAD of embedded systems
System level performance/power/thermal modeling and System level performance/power/thermal modeling and optimizationoptimization
Synthesis – scheduling and allocation, logic optimization Synthesis – scheduling and allocation, logic optimization and technology mappingand technology mapping
FPGA circuits and architectures and placement and FPGA circuits and architectures and placement and routing for FPGArouting for FPGA
EE205B Modeling and Optimization for VLSI EE205B Modeling and Optimization for VLSI layoutlayout Advanced algorithms for physical designAdvanced algorithms for physical design
Fundamentals of combinatorial algorithmFundamentals of combinatorial algorithm Detailed performance, signal integrity, power and thermal Detailed performance, signal integrity, power and thermal
modelsmodels Incorporating physical design into system designIncorporating physical design into system design
System Specification
Functional Design
Logic Design
Circuit Design
X=(AB*CD)+(A+D)+(A(B+C))
Y=(A(B+C))+AC+D+A(BC+D))
VLSI Design Cycle
Physical Design
Fabrication
Packaging
VLSI Design Cycle (cont.)
Partition
Floorplanning
Placement
Simplified Physical Design Cycle
Routing
Extraction and Verification
Front-endFront-end
physical designphysical design
Back-endBack-end
physical designphysical design
Course Outline and Schedule
Front-end physical design (4.5 weeks)Front-end physical design (4.5 weeks) Partitioning, floorplanning and placementPartitioning, floorplanning and placement Power and thermal modelingPower and thermal modeling Algorithms: divided and conquer, simulated annealing, genetic algorithmAlgorithms: divided and conquer, simulated annealing, genetic algorithm Project proposal due by end of fifth weekProject proposal due by end of fifth week
Back-end physical design (4.5 weeks)Back-end physical design (4.5 weeks) Interconnect extraction and modeling Interconnect extraction and modeling Interconnect synthesisInterconnect synthesis Noise modeling and avoidanceNoise modeling and avoidance Clock and power supply design **Clock and power supply design ** Algorithms: dynamic programming, linear programmingAlgorithms: dynamic programming, linear programming Project report due the last day of the quarterProject report due the last day of the quarter
ACM IEEE Design Automation Conference (DAC)
http://www.dac.com (San Diego, Young student program)
International Conference on Computer Aided Design(ICCAD)
Design, Automation and Test in Europe (DATE)
Asia and South Pacific Design Automation Conference (ASP-DAC)
International symposium on physical design (ISPD)
International symposium on low power electronics and design
International symposium on field programmable gate array
IEEE International Symposium on Circuits and Systems (ISCAS)
Related VLSI CAD Conferences
IEEE Transactions on CAD of Circuits and systems (TCAD)
ACM Trans. on Design Automation of Electronic Systems (TODAES)
IEEE Transactions on Circuits and Systems (TCAS)
IEEE Trans. on VLSI Systems (TVLSI)
IEEE Trans. on Computer
Integration
Algorithmica
SIAM journal of Discrete and Applied Mathematics
Related VLSI CAD Journals
Synposys, Cadence, Magma, Mentor Graphics, …
Over hundreds companies have booths at DAC
Two of them are among the ten biggest software companies in the world
But they are smaller than the biggest spin-off of EDA
EDA is regarded as A-graded bonds for Venture Capitalists
One of few IT segments still recruits heavily and offers salary higher than Intel/IBM
EDA system is regarded as one of the most complicated software systems mankind ever built
Money Talk for VLSI CAD
References for this Course
Selected papers from TCAD, TODAES, and major CAD Selected papers from TCAD, TODAES, and major CAD conferences such as DAC, ICCAD and ISPDconferences such as DAC, ICCAD and ISPD
Naveed A. Sherwani, "Algorithms for VLSI Physical Design Naveed A. Sherwani, "Algorithms for VLSI Physical Design Automation", 3rd Edition, 1998.Automation", 3rd Edition, 1998.
H. Cormen, et al “Introduction to Algorithms” MIT H. Cormen, et al “Introduction to Algorithms” MIT Electrical Engineering and Computer Science Series 1990.Electrical Engineering and Computer Science Series 1990.
H. Bakoglu, H. Bakoglu, Circuits, Interconnects, and Packaging for VLSICircuits, Interconnects, and Packaging for VLSI, , Addison WesleyAddison Wesley
Cong et al., Performance Optimization of VLSI Interconnect Cong et al., Performance Optimization of VLSI Interconnect Layout, Layout, Integration, the VLSI JournalIntegration, the VLSI Journal 21 (1996) 1--94. 21 (1996) 1--94.
Grading Policy
HomeworkHomework 15%15% Midterm (7Midterm (7thth week) week) 20%20% Course presentationCourse presentation 15%15% Term projectTerm project 50%50%
A A score > 85 and programming project score > 85 and programming project
Course Presentation (15%)
2~3 student a team2~3 student a team Survey an area (topics and resources specified by me Survey an area (topics and resources specified by me
on a continual basis)on a continual basis) Prepare slides and do a 30-35 minute presentation in Prepare slides and do a 30-35 minute presentation in
the classthe class slides prepared jointlyslides prepared jointly either all students share the presentation or I will select the either all students share the presentation or I will select the
speaker randomly at the presentation timespeaker randomly at the presentation time
Prepare a web site that should contain a report based Prepare a web site that should contain a report based on your survey, a bibliography, and links to resources on your survey, a bibliography, and links to resources and of course your slidesand of course your slides
Term Project (50%)
One of the following two:One of the following two: One-person survey and critic of selected topic (at most 35%)One-person survey and critic of selected topic (at most 35%) Individual programming project for a team of 2 to 3 personsIndividual programming project for a team of 2 to 3 persons
Coupled system design and physical designCoupled system design and physical design Floorplanning with thermal constraintsFloorplanning with thermal constraints 3D modeling and physical design3D modeling and physical design Or any topic agreed by instructorOr any topic agreed by instructor
Up to 30 minute presentation during the finals week, Up to 30 minute presentation during the finals week, like a conference talk like a conference talk
Up to 12 page report in the style of a technical Up to 12 page report in the style of a technical conference paperconference paper
ACM style ACM style http://www.acm.org/sigs/pubs/proceed/template.htmhttp://www.acm.org/sigs/pubs/proceed/template.htm
Who should take this course
It is another courseIt is another course Discuss wide scope of knowledgeDiscuss wide scope of knowledge But research (presentation + project) on your But research (presentation + project) on your
own focusown focus
For students who are motivated toFor students who are motivated to Learn SI, power/thermal for advanced designsLearn SI, power/thermal for advanced designs Learn algorithm basics without taking CS280Learn algorithm basics without taking CS280 Understand CAD betterUnderstand CAD better Become a CAD professionalBecome a CAD professional
More than 10 million transistor
Performance driven designs
Time-to-Market
Design cycle
High performance, high cost
…...
Complexities of Physical Design
Technology (um) 0.25 0.18 0.15 0.13 0.10 0.07Year 1997 1999 2001 2003 2006 2009
# transistors 11M 21M 40M 76M 200M 520MOn-Chip Clock (MHz) 750 1200 1400 1600 2000 2500
Area (mm2) 300 340 385 430 520 620Wiring Levels 6 6-7 7 7 7-8 8-9
Moore’s Law and NTRS
Moore’s LawMoore’s Law The min. transistor feature size decreases by 0.7X every three The min. transistor feature size decreases by 0.7X every three
years (Electronics Magazine, Vol. 38, April 1965)years (Electronics Magazine, Vol. 38, April 1965) True in the past 30 years, and expected to hold for another 10-True in the past 30 years, and expected to hold for another 10-
15 years15 years National Technology Roadmap for Semiconductors National Technology Roadmap for Semiconductors
(NTRS’97)(NTRS’97)
Productivity Gap
xxx
xxx
x 21%/Yr. Productivity growth rate
x
58%/Yr. Complexity growth rate
1
10
100
1,000
10,000
100,000
1,000,000
10,000,000
199810
100
1,000
10,000
100,000
1,000,000
10,000,000
100,000,000
Lo
gic
Tra
nsi
sto
rs/C
hip
(K
)
Tra
nsi
sto
r/S
taff
-Mo
nth
Chip Capacity and Designer Productivity
2003
Source: NTRS’97
Design Challenges in Nanometer Technologies
Interconnect-limited designsInterconnect-limited designs Interconnect performance limitationInterconnect performance limitation Interconnect modeling complexityInterconnect modeling complexity Interconnect reliabilityInterconnect reliability Impact of new interconnect materialsImpact of new interconnect materials
Small feature sizeSmall feature size Process variationsProcess variations Leakage (~50% of total power)Leakage (~50% of total power)
High degree of on-chip integrationHigh degree of on-chip integration Complexity and productivityComplexity and productivity Limitation of current design abstraction and hierarchyLimitation of current design abstraction and hierarchy System on a chip and system in package or 3D technologySystem on a chip and system in package or 3D technology Power/thermal barrierPower/thermal barrier
Complexity of VLSI circuits
Full custom
Performance Size Cost Market time
Standard Cell Gate Array FPGA
Different design styles
Cost ,Flexibility,Performance
Design Styles
Full Custom Design StylePad Metal Via Metal 2
I/OData Path
ROM/RAM
PLA
A/D ConverterRandom logic
Standard Cell Design StyleVDD Metal 1
CellMetal 2
FeedthroughGND
D C C B
A C C
D C D B
C C C B
Cell A
Cell C
Cell B
Cell D Feedthrough cell
Gate Array Design Style (or Structured ASIC)
A
B
C
A
B
C
VDD Metal1 Metal2
Programmable logic Programmable interconnects Programmable inputs/outputs
Field-Programmable Gate-Arrays (FPGAs)
FPGA Design Style
Comparisons of Design Styles
full-custom standard cell gate array FPGA
cell size variable fixed height * fixed fixed
cell type variable variable fixed programmable
cell placement variable in row fixed fixed
interconnections variable variable variable programmable
* uneven height cells are also used
style
Area
Performance
Fabrication layers
style
full-custom standard cell gate array FPGA
compact
high
compact
to moderatemoderate large
high to moderate
moderate low
ALL ALL routing layers
none
Comparisons of Design Styles
Printed Circuit Board PCB
Multi-Chip Module MCM
Wafer Scale Integration WSI or 3D
Packaging
Area
Performance, cost
The increasing complexity and density of the semiconductor devices are driving the development of more advanced VLSI packaging and interconnection approaches.
Packaging Styles
Printed Circuit Board Model
Large number of layers (150a pitch)
Larger area
Low performance
Low cost
PackagePlated through holes
IC ( a )
( b )
MCM Model
Up to 36 layers ( 75a pitch)
Moderate to small area
Moderate to high performance
High cost
Heat dissipation problems
IC ( a )
( b )
Wafer Scale Integration
Small number of layers (VLSI technology- 6a pitch)
Smallest area
Significant yield problems
Very high performance
Significant heat dissipation problems
Comparisons of Packaging Styles
Technology Figure of Merit
(inches/psec. density inches/sq in)
WSI
MCM
PCB
28.0
14.6
2.2
Merit = propagation speed (inches/psec.) * interconnection density (inches/sq. in). Interconnect resistance was not considered
Increasingly on the Same Chip or in the Same Package (SoC and SiP)
SC3001 DIRAC chip (Sirius Communications)SC3001 DIRAC chip (Sirius Communications)
History of VLSI Layout ToolsYear Design Tools
1950 - 1965
1965 - 1975
1975 - 1985
1985 – 1995
1995 -- present
Manual Design
Layout editorsAutomatic routers( for PCB)Efficient partitioning algorithm
Automatic placement toolsWell Defined phases of design of circuitsSignificant theoretical development in all phases
Performance driven placement and routing toolsParallel algorithms for physical designSignificant development in underlying graph theoryCombinatorial optimization problems for layout
Interconnect layout optimization, Interconnect-centric design, physical-logical codesign
One of the new trends: SoC and SiP for 3D technology
Summary Physical design is the most complicated step in the VLSI design Physical design is the most complicated step in the VLSI design
cyclecycle
Physical design is further divided into clustering, partitioning, Physical design is further divided into clustering, partitioning, floorplanning, placement, global and detailed routing. Extraction floorplanning, placement, global and detailed routing. Extraction and verification is an important aspect.and verification is an important aspect.
There are four major design styles -- full custom, standard cell, There are four major design styles -- full custom, standard cell, gate array (structured ASIC), and FPGAs.gate array (structured ASIC), and FPGAs.
There are three alternatives for packaging of chips -- PCB, MCM There are three alternatives for packaging of chips -- PCB, MCM and WSI. But increasingly, we design for SoC and SiP and will use and WSI. But increasingly, we design for SoC and SiP and will use 3D technology3D technology
Automation reduces cost, increases chip density, reduces time-Automation reduces cost, increases chip density, reduces time-to-market, and improves performance.to-market, and improves performance.
CAD tools currently lag behind fabrication technology, which is CAD tools currently lag behind fabrication technology, which is hindering the progress of IC technologyhindering the progress of IC technology
Homework (due April 14th) Read ITRS roadmap executive summary and write one page Read ITRS roadmap executive summary and write one page
summary and critic on one aspect related to your research or summary and critic on one aspect related to your research or fieldfield http://public.itrs.net/Files/2001ITRS/Home.htmhttp://public.itrs.net/Files/2001ITRS/Home.htm
Search literature or web related to SoC, SiP and 3D technology, Search literature or web related to SoC, SiP and 3D technology, summarize five papers on a coherent topic (e.g., technology, summarize five papers on a coherent topic (e.g., technology, design, or CAD) and speculate potential need of CAD researchdesign, or CAD) and speculate potential need of CAD research Following style of conference paperFollowing style of conference paper
With course project proposal in mindWith course project proposal in mind
Submit homework in PDF via emailSubmit homework in PDF via email
Check out course website for notes of future lecturesCheck out course website for notes of future lectures http://eda.ee.ucla.edu/EE201A-04Springhttp://eda.ee.ucla.edu/EE201A-04Spring