CSCE 932, Spring 2007 Fault Tolerance: Testing and Testable Design

1. CSCE 932, Spring 2007Fault Tolerance: Testing and Testable Design Course Overview

2. About Myself • Professor in CSE/UNL since 1970 • Teach (among others): • VLSI Testing (932) • VLSI Design (434/834) • Senior Design (488-489) • Computer Organization (230),

3. VLSI Testing Imperfect chip manufacturing Coverage metrics for high-volume manufacutring Complexity of defects and algorithms My Current Research Double-Tree Scan DTS(2) CLK L1 L2 Handwriting Recognition • A new general paradigm for recognizing difficult-to-segment patterns without requiring training GIS • Conflation: Combining information from different sources • High-resolution satellite image analysis of urban images for planning growth, etc.

4. Outline • Fault Tolerance • Technological Trends • Course Topics and Organization

5. Fault Tolerance • Ability of a system to function in the event of a failure • Sources of Failure • Permanent (hard) component failures causing system malfunction • Transient failures due to internal or external causes • Unreliable components • Buggy software • Radiation, Noise, Crosstalk • ...

6. Fault Tolerance Methods • Redundancy Techniques • Component (HW or SW) Level • Information Level • Frequent Testing and Possible Repair • Online testing • Offline testing This course will focus on fault tolerance through testing of digital components

7. Types of Testing • During Design & Manufacturing • Design Verification (Validation) • Process Characterization • Silicon Debug • Production (Go/No-Go) • Beyond Manufacturing • Acceptance • Power-on • Field test and repair We will focus on design & manufacturing testing

8. Technological Trends (See ITRS 2005 for details)

9. Trends of Interest to Us • Embedded systems and chip or core multiprocessors (CMPs) • Importance of low power in high-volume and high-performance devices and systems • Feature Size Reduction • Design productivity and time-to-market • Wiring delays dominate gate delays

10. Number of Processors Sold by Computing Applications Desktops and Servers market is relatively flat, Embedded growing quickly. The trend is likely to continue.

11. Sales of Microprocessors by Instruction Set Architecture ARM is a RISC processor commonly used as a core. IA-32 and IA-64 are very competitive in desktops and notebooks. “Other” are application-specific or custom designs

12. IC Types and Requirements Determined by Portable/Consumer Market • Three major types (as identified by ITRS 2005) • SOC • Low-power paramount • Need SOC integration (DSP, MPU, I/O Cores, NoC, etc.) • Analog/Mixed Signal • Migrating on-chip for voice processing, A/D sampling, and some RF transceiver functions • MPU • Specialized cores to optimize performance for low-power use.

13. Feature Size (From ITRS 2005) • MPU Printed Gate Length nm (Near Term) • MPU Printed Gate Length nm (Long Term)

14. Typical Production Ramp-Up Curve (ITRS-2005)

15. Power-Efficient SOC Requirements (ITRS-2005)

16. Design Productivity Trends for Power-Efficient SOCs. To solve the challenging productivity improvement requirement, ITRS-2005 recommends: • Design abstraction level must be raised • Level of automation in design verification and implementation must be increased • Design overhead of reuse must be targeted for reduction – it is not enough to increase the design reuse.

17. Course Topics and Organization • Background in VLSI Testing (first half of the course – by me) • Basics • Fault Modeling • Coverage Analysis • Test Generation • Design for Testability • Current topics (presentations and discussions by all) (second half of the course) • Individual Research Projects (second half of the course)