The document outlines a mini-project on implementing hybrid cellular automata for testing patterns and compacting responses in VLSI design. It discusses objectives, working principles, advantages, disadvantages, and potential applications of the technology. Key topics include the importance of testing in VLSI design, the use of built-in self-test methodologies, and future extensions related to self-repair and programmable memory testing.

1. ECE-DEPARTMENT
1. SHIVA SHANKER BEERAVELLI : 10T81A0448
2. PALUSA KRANTHI KUMAR GOUD : 10T81A0417
3. G.SHIVA NARAYANA REDDY : 10T81A0449
4. SHEELAM RAMU : 10T81A0431
Internal Guide:
Mr.K.ASHOK KUMAR
Assoc. Prof & HOD-ECE

2. A MINI-PROJECT
ON
IMPLEMENTATION OF
HYBRID CELLULAR AUTOMATA AS A TEST
PATTERN GENERATER & RESPONSE COMPACTOR
FOR BIST

3. CONTENTS:
 Objective
 Working Principles
 Diagrammatic View
 Advantages /Disadvantages With Examples
 Applications in Real Time Scenario
 Future Extension of the Project
 Summary
 References /Bibliography

4.  WHY TESTING IS IMPORTANT IN VLSI
DESIGN ?
 Specifications
 Code designing
 Code verification
 RTL designing
 Simulation
 Synthesis
 Fabrication
TESTING
 packing
PROBLEM:
Testing of circuits in past was done
by ATE

5. PRESENT APPROACH FOR TESTING:
(DFT-DESIGN FOR TESTABILITY)
 BUILT-IN-SELF TEST
 BIST eliminating the dependence on an external
automated test equipment (ATE)
Block Diagram shows TESTING Process
Seed value
Seed value
din
Good/fault

6. MAIN OBJECTIVE:
 To construct the TPG
 To construct the ORA
Using CELLULAR AUTOMATA (CA)
Pseudo random
generator

7. CELLULAR AUTOMATA:
 Cellular automata is collection of cells with regular
collections.
Working Principles/Rules:
 Each cell connects to its local neighbors by using
rule 90 and rule150.
Flip-flops

8.  Rule 90:  Rule 150:
 Transition function [rule 90] : Xc(t+1) = Xc-1(t) xor Xc+1(t).
 Transition function [rule 150]: Xc(t+1) = Xc-1(t) xor Xc(t) xor Xc+1(t).
C-1 : past
C : present
C+1 : future
Diagrammatic View:

9. Cellular automata as a TEST PATTERN GENERATER :

10.  CA produces (2^n-1) test patterns automatically.

11. Cellular automata as a RESPONSE COMPACTOR:
din din
din
din
din

12.  Lower cost of test, since the need for external electrical
testing using an ATE will be reduced, if not eliminated.
 better fault coverage, since special test structures can be
incorporated onto the chips.
 easier customer support.
 capability to perform tests outside the production electrical
testing environment.
 Shorter test times if the BIST can be designed to test more
structures in parallel.
Advantages:

13.  additional silicon area and fob processing requirements .
 additional pin requirements.(since the BIST circuitry need a way to
interface with the outside world to be effective)
 possibly bigger package size
Disadvantages:

14.  Integrated circuit manufacture :BIST is used to make faster,
less-expensive integrated circuit manufacturing tests.
 Computers(pc’s test itself at startup)
 Medicine (medical devices test themselves to assure continued
safety )
 Military (used in missiles where the bist is computer c
controlled)
Applications in Real Time Scenario :

15. Future Extension of the Project:
•Built-In Self-Repair (BISR).
•Transparent BIST for RAMs.
•Programmable memory BIST.

17. References /Bibliography:
1. Bushnell and Agrawal, “Essentials of Electronic Testing for
Digital, Memory & Mixed-Signal VLSI Circuits” New York:
Kluwer Academic Publishers, 2002
2. Serra, M.; Slater, T.; Muzio, J.C.; Miller, D.M., “The
analysis of one-dimensional linear cellular automata and
their aliasing properties, IEEE Transactions on, Volume: 9 ,
Issue: 7 , July 1999, Pages:767 – 778.
3. Jianbing Zhao., “A Novel FPGA Manufacture-oriented
Interconnect Fault Test,” 9th International Conference on
Solid-State and Integrated-Circuit Technology, 2008