ESE 370 CircuitLevel Modeling Design and Optimization for

ESE 370: Circuit-Level Modeling, Design, and Optimization for Digital Systems Day 1: September 5, 2012 Introduction and Overview Penn ESE 370 Fall 2012 -- De. Hon 1

Questions • How fast can my computer run? – What limits this speed? – What can I do to make it run faster? • How can I extend the battery life on my gadget? – How much energy must my computation take? • How small can I make a memory? – Why does DRAM need to be refreshed? Penn ESE 370 Fall 2012 -- De. Hon 2

Questions • How many bits/second can I send over a link? – What limits this? – How do I maximize? • How does technology scaling change these answers? • What can I rely on technology to deliver? Penn ESE 370 Fall 2012 -- De. Hon 3

Sample Problems Penn ESE 370 Fall 2012 -- De. Hon 4

What does this circuit do? How fast does it operate? Penn ESE 370 Fall 2012 -- De. Hon 5

What’s wrong here? How fix? Penn ESE 370 Fall 2012 -- De. Hon 6

Limits? • • Consider a 45 nm technology Typical gate with W=3, 2 -input NOR Use chip in cell phone What prevents us from running 1 billion transistor chip at 10 GHz? Penn ESE 370 Fall 2012 -- De. Hon 7

Impact of Voltage? • If have a chip running at 1 GHz with a 1 V power supply dissipating 1 W. • What happens if we cut the power supply to 500 m. V? – Speed? – Power? Penn ESE 370 Fall 2012 -- De. Hon 8

Outline • • Motivating Questions What this course is about Objectives What you need to know Structure Policies Content Penn ESE 370 Fall 2012 -- De. Hon 9

Deconstruction • Circuit-Level Modeling, Design, and Optimization for Digital Systems Look below the gates …transistors, resistance, capacitance, inductance… Abstract and predict Create Make efficient (fast, low energy, small) Compute, store, transmit binary values (0 s, 1 s) Penn ESE 370 Fall 2012 -- De. Hon 10

What course about • What Computer Engineers need to know about the physical properties in order to design efficient digital circuits • Physical Properties – Delay, Energy (Power), Area, Reliability • Efficient – Fast, Low Energy, Small, Won’t Fail (very often) • Digital Circuits – Computation, Storage, Communication Penn ESE 370 Fall 2012 -- De. Hon 11

What course is about • Modeling and abstraction – Predict circuit behavior – Well enough to know our design will work – …with specific properties • Speed, energy, …. – Well enough to reason about design and optimization • What knob can I turn to make faster? • How much faster can I expect to make it? Penn ESE 370 Fall 2012 -- De. Hon 12

What course is about • Modeling and abstraction – Back-of-the-envelope • Simple enough to reason about – …without a calculator… – Sensitive to phenomenology • Able to think through the details – With computer assistance • …understanding even that is a simplified approximation Penn ESE 370 Fall 2012 -- De. Hon 13

CIS 120 CIS 380 CIS 240 CIS 371, ESE 534 ESE 170 (ESE 200) You are here. ESE 205/215, ESE 319 ESE 218 Penn ESE 370 Fall 2012 -- De. Hon Phys 151 14

Objectives Penn ESE 370 Fall 2012 -- De. Hon 15

You will learn • disciplines for robust digital logic and signaling – (e. g. , restoration, clocking) • where delay, energy, area, and noise arises in gates, memory, and interconnect • how to model these physical effects – back-of-the-envelope design • (e. g. RC and Elmore delay) – detailed simulation (e. g. SPICE) Penn ESE 370 Fall 2012 -- De. Hon 16

You will learn • the nature of tradeoffs in optimization – Among delay, energy, area, noise • how to design and optimize – logic, memory, and interconnect structures – at the gate, transistor, and wire level • how technology scales – and its impact on digital circuits and computer systems Penn ESE 370 Fall 2012 -- De. Hon 17

What you Need to Know coming in to this course Penn ESE 370 Fall 2012 -- De. Hon 18

What you need to know • See pages linked from course page • CIS 170 – Gates, Boolean logic, De. Morgan’s, optimization • CIS 215 – RLC circuit analysis – Diagnostic Quiz next time – end of class Penn ESE 370 Fall 2012 -- De. Hon 19

Review Session Poll Tonight in Ketterer Will work? • 5 pm • 6 pm • 7 pm • 8 pm Also poll TA hour M & W during rest of term. Penn ESE 370 Fall 2012 -- De. Hon 20

Structure Penn ESE 370 Fall 2012 -- De. Hon 21

Structure • MWF Lecture • Reading from text • 4 lecture periods Lab – 3 Detkin • See phenomena first hand before simulate – 1 Ketterer SPICE Intro Penn ESE 370 Fall 2012 -- De. Hon 22

SPICE • Simulation Program with Integrated Circuit Emphasis – Industry standard analog circuit simulator – Non-linear, differential equation solver specialized for circuits • Integrated circuits – simply impractical to build to debug – Must simulate to optimize/validate design Penn ESE 370 Fall 2012 -- De. Hon 23

Structures • Homeworks – week long (7 total) • Projects – two weeks long (2 total) – Design oriented – On two main topics • Computation • Storage • Two midterms • Final Penn ESE 370 Fall 2012 -- De. Hon 24

Admin • Won’t bring printouts to class • Use course calendar – Lectures online before class • (most of the time) – Homeworks linked • Homework 1 out now (tied to first lab visit) – Reading specified Penn ESE 370 Fall 2012 -- De. Hon 25

Policies Penn ESE 370 Fall 2012 -- De. Hon 26

Policies See web page for details • Turnin homework on blackboard – No handwritten homework – Use CAD Tools for circuit drawings • Late homework penalty • Individual work (HW & Project) – CAD drawings, simulations, analysis, writeups – May discuss strategies, but must acknowledge Penn ESE 370 Fall 2012 -- De. Hon 27

Content Penn ESE 370 Fall 2012 -- De. Hon 28

Content • Logic (Computation) [7 weeks] – Combinational – Sequential • Storage • Communication Penn ESE 370 Fall 2012 -- De. Hon [2 weeks] [3 weeks] 29

Content • Logic – Transistors Gates – In Lab: build gate, measure delay, restore – Restoration – Delay – Area (no layout ESE 570) – Energy – Synchronous (flip-flops, clocking, dynamic) – Project: fast ripple-carry adder Penn ESE 370 Fall 2012 -- De. Hon 30

Content • Memory – No Lab component – RAM Organization – Driving Large Capacitances – Signal amplification/restoration – Project: design a SRAM Register File Penn ESE 370 Fall 2012 -- De. Hon 31

Content • Communication – In Lab • Measure inductive ground bounce, crosstalk • Experiment with transmissions lines, termination – Noise • Crosstalk • Inductive • Ionizing particles, shot – Transmission Lines Penn ESE 370 Fall 2012 -- De. Hon 32

Advice • Course is hard (but valuable) • Must read text • Learning is spread over all components – Lecture, reading, homeworks, projects, exams • Must be able to get quantitative answers to get an A (maybe even for B) Penn ESE 370 Fall 2012 -- De. Hon 33

Wrapup • Admin – Find web, get text, assigned reading… – http: //www. seas. upenn. edu/~ese 370 – Piazza https: //piazza. com/upenn/fall 2012/ese 370/ home • Big Ideas / takeaway – Model to enable design • Diagnostic Quiz next time – Review as needed • Remaining Questions? Penn ESE 370 Fall 2012 -- De. Hon 34