EE141 © Digital Integrated Circuits2nd Introduction

An Introduction to VLSI (Very Large Scale Integrated)

Circuit Design

Presented at EE1001 Oct. 16th, 2012

By Hua Tang

EE141 © Digital Integrated Circuits2nd Introduction 2

The First Computer

The BabbageDifference Engine(1832)

25,000 parts

cost: £17,470

EE141 © Digital Integrated Circuits2nd Introduction 3

The first electronic computer (1946)

EE141 © Digital Integrated Circuits2nd Introduction

First transistor

Bell Labs, 1948

First Transistor (Bipolar)

EE141 © Digital Integrated Circuits2nd Introduction 5

The First Integrated Circuits

Bipolar logic

1960’s

ECL 3-input Gate

Motorola 1966

EE141 © Digital Integrated Circuits2nd Introduction

Basic IC circuit component: MOS transistor MOS: Metal Oxide Semiconductor

EE141 © Digital Integrated Circuits2nd Introduction 7

Intel 4004 Micro-Processor

1971

1000 transistors

< 1MHz operation

10μm technology

EE141 © Digital Integrated Circuits2nd Introduction 8

Intel Pentium (IV) microprocessor

2001

42 Million transistors

1.5 GHz operation

0.18μm technology

EE141 © Digital Integrated Circuits2nd Introduction 9

More recent Processors 2006

291 Million transistors

3 GHz operation

65nm technology

2007

800 Million transistors

2 GHz operation

45nm technology (the biggest change in CMOS transistor

technologies in 40 years)

2010 Core i7

1.2 Billion transistors

3.3 GHz operation

32nm technology

EE141 © Digital Integrated Circuits2nd Introduction

Moore’s Law

In 1965, Gordon Moore noted that the

number of transistors on a chip doubled

every 18 to 24 months.

He made a prediction that

semiconductor technology will double its

effectiveness every 18 months

EE141 © Digital Integrated Circuits2nd Introduction

Moore’s law in Microprocessors

4004 8008

8080 8085 8086

286 386

486 Pentium® proc

P6

0.001

0.01

0.1

1

10

100

1000

1970 1980 1990 2000 2010

Year

Tra

nsis

tors

(M

T)

2X growth in 1.96 years!

Transistors on Lead Microprocessors double every 2 years

Courtesy, Intel

EE141 © Digital Integrated Circuits2nd Introduction

Frequency

P6

Pentium ® proc 486

386 286 8086 8085

8080

8008 4004

0.1

1

10

100

1000

10000

1970 1980 1990 2000 2010

Year

Fre

qu

en

cy (

Mh

z)

Lead Microprocessors frequency doubles every 2 years

Doubles every

2 years

Courtesy, Intel

EE141 © Digital Integrated Circuits2nd Introduction

Not Only Microprocessors

Analog

Baseband

Digital Baseband

(DSP + MCU)

Power

Management

Small

Signal RF Power

RF

Cell Phone

HDTV

PDA

….

EE141 © Digital Integrated Circuits2nd Introduction

What is a MOS Transistor?

VGS VT

Ron

S D

A Switch!

|V GS |

An MOS Transistor

EE141 © Digital Integrated Circuits2nd Introduction

MOS Transistors - Types and Symbols

D

S

G

G

S

D

NMOS

PMOS

if G=“0” or ground

switch on

if G=“1” or Vdd

switch on

EE141 © Digital Integrated Circuits2nd Introduction

The CMOS Inverter: A First Glance

V in V out

C L

V DD

EE141 © Digital Integrated Circuits2nd Introduction

CMOS Inverter

First-Order DC Analysis

V DD V DD

V in = V DD V in = 0

V =0 out

V =V out

R n

R p

DD

EE141 © Digital Integrated Circuits2nd Introduction

0 0.5 1 1.5 2 2.5

x 10-10

-0.5

0

0.5

1

1.5

2

2.5

3

t (sec)

Vout(V

)

Transient Response

tpLH tpHL

The delay

Essentially

determines the

clock speed of the

processor

EE141 © Digital Integrated Circuits2nd Introduction

Static CMOS (Complementary MOS) VDD

F(In1,In2,…InN)

In1

In2

InN

In1

In2

InN

PUN

PDN

PMOS only

NMOS only

PUN and PDN are dual logic networks

EE141 © Digital Integrated Circuits2nd Introduction

NMOS Transistors

in Series/Parallel Connection

Transistors can be thought as a switch controlled by its gate signal

NMOS switch closes when switch control input is high

X Y

A B

Y = X if A and B

XY

A

B Y = X if A OR B

NMOS Transistors pass a “strong” 0 but a “weak” 1

EE141 © Digital Integrated Circuits2nd Introduction

PMOS Transistors

in Series/Parallel Connection

X Y

A B

Y = X if A AND B = A + B

XY

A

B Y = X if A OR B = AB

PMOS Transistors pass a “strong” 1 but a “weak” 0

PMOS switch closes when switch control input is low

EE141 © Digital Integrated Circuits2nd Introduction

Example Gate: NAND

EE141 © Digital Integrated Circuits2nd Introduction

Example Gate: NOR

EE141 © Digital Integrated Circuits2nd Introduction

Full-Adder A B

Cout

Sum

Cin Fulladder

EE141 © Digital Integrated Circuits2nd Introduction

The Binary Adder

S A B Ci

=

A= BCi ABCi ABCi

ABCi

+ + +

Co

AB BCi

ACi

+ +=

A B

Cout

Sum

Cin Fulladder

EE141 © Digital Integrated Circuits2nd Introduction

Complimentary Static CMOS Full Adder

28 Transistors

A B

B

A

Ci

Ci A

X

VDD

VDD

A B

Ci BA

B VDD

A

B

Ci

Ci

A

B

A CiB

Co

VDD

S

EE141 © Digital Integrated Circuits2nd Introduction

The Ripple-Carry Adder

FA FA FA FA

A0 B0

S0

A1 B1

S1

A2 B2

S2

A3 B3

S3

Ci,0 Co,0

(= Ci,1)

Co,1 Co,2 Co,3

EE141 © Digital Integrated Circuits2nd Introduction

SRAM Memory cell

EE141 © Digital Integrated Circuits2nd Introduction

The add-up

32-bit adder: >3,000

32-bit comparator: >3,000

32-bit multiplier: >50,000

1k SRAM: 6,000

…

EE141 © Digital Integrated Circuits2nd Introduction

Design Metrics

How to evaluate performance of a digital circuit (gate, block, …)?

Cost

Reliability

Scalability

Speed (delay, operating frequency)

Power dissipation

Energy to perform a function

EE141 © Digital Integrated Circuits2nd Introduction

Future Design Challenges

Processor architecture (multiple-core; interconnections)

Semi-conductor materials (current leakage; process variation)

Power consumption (power density; thermal dissipation)

EE141 © Digital Integrated Circuits2nd Introduction

Career in VLSI design VLSI circuit design and design automation

Intel, IBM, AMD, Texas Ins., Agilent,…

Qualcomm, Broadcom, Samsung,…

Micron, Seagate, WesternDigital…

Cadence, Synopsys, MentorGraphics…

Xilinx, Altera, ….

....

EE141 © Digital Integrated Circuits2nd Introduction

VLSI Design: FFT Butterfly

Widely used in signal

processing

Design Butterfly Unit

for 2-point FFT

Components include

multiplier, adder,

subtractor, and data

management

8-point FFT composed of 12 butterflies

Image from www.cmlab.csie.ntu.edu.tw/cml/dsp/training/coding/transform/fft.html

By: Spencer Strunic

Matt Webb

EE141 © Digital Integrated Circuits2nd Introduction

FFT Butterfly Unit Layout

EE141 © Digital Integrated Circuits2nd Introduction

Registers

Store data

Manipulate data

ALU

Select between many different operations to output

Adder

Adds two 8-bit numbers

Multiplier

Multiplies two 8-bit numbers

By: Brian Linder

Matt Leines

VLSI Design: 8-bit CPU

EE141 © Digital Integrated Circuits2nd Introduction

8-bit CPU Layout

EE141 © Digital Integrated Circuits2nd Introduction

FIR Filter

FIR – Finite-Impulse Response Involves calculations of finite convolution

sums in discrete-time systems Useful for Digital Signal Processing Equation -

x is the input signal, h is the finite impulse response, y is the sum output and N is the order of the filter

By: Craig Bristow

Joliot Chu

EE141 © Digital Integrated Circuits2nd Introduction

FIR Filter System Design

x[n]h[k]:

CONT

ROL

Module 1 – Control Module

INPUT STORAGE

Module 2 – Input Module

COEFFICIENTS

STORAGE

Module 3 – Coefficients Module

ARITHMETIC

Module 4 – Arithmetic Module

RESULTS

STORAGE

Module 5 – Results Storage

EE141 © Digital Integrated Circuits2nd Introduction

A Delta-Sigma Converter for WCDMA

By: Matt Webb, Hairong Chang

EE141 © Digital Integrated Circuits2nd Introduction

Nowdays, many electronic systems on a single chip have both analog and digital (called Mixed-signal SoC (System on Chip))

From Texas

Instruments

EE141 © Digital Integrated Circuits2nd Introduction 41

EE141 © Digital Integrated Circuits2nd Introduction

Contact Information:

Office: MWAH 276

Hour: 3-5pm MW

Phone: 726-7095

Email: htang@d.umn.edu

Http: www.d.umn.edu/~htang