1. BIST Pattern Generator inserter using Cellular Automata By Jeffrey Dwoskin Project for Testing of ULSI Circuits, Spring 2002, Rutgers University 5/15/02

2. 5/15/2002 Jeffrey Dwoskin - BIST Pattern Generator - Testing of ULSI Circuits - Spring 20022 Purpose To add BIST hardware to a combinational circuit Circuit input & output in Rutmod format Pattern Generator uses Cellular Automata, using rule 90 & 150 cells

3. 5/15/2002 Jeffrey Dwoskin - BIST Pattern Generator - Testing of ULSI Circuits - Spring 20023 Algorithm Read in netlist in Rutmod format Determine number of Primary Inputs Find a maximal length CA with the correct number of cells Add a PI for the test control signal For each PI in original circuit: Create a new CA cell using either rule 90 or 150 depending on the CA we chose earlier Connect output of current cell to input of previous cell Connect output of previous cell to input of current cell Add a MUX to the Primary Input. 0 input is the original PI, 1 input comes from the new CA cell. The MUX is controlled by the test control input

4. 5/15/2002 Jeffrey Dwoskin - BIST Pattern Generator - Testing of ULSI Circuits - Spring 20024 Algorithm Find a maximal length CA with the number of cells = number of POs For each PO in the circuit Create a new CA cell using either rule 90 or 150 depending on the CA we chose earlier Connect output of current cell to input of previous cell Connect output of previous cell to input of current cell Connect input to PO to the input of the cell Add a MUX to the PO output. 0 is the original source of the PO and 1 is the output of the response compactor. The MUX is controlled by the test control input

5. 5/15/2002 Jeffrey Dwoskin - BIST Pattern Generator - Testing of ULSI Circuits - Spring 20025 Finding Maximal Length CA’s There are many possible Maximal length CA’s for a given number of cells. We want to use only rule 90 and rule 150 cells. Rule 90 cells use less hardware and are preferred Minimal Cost One-Dimensional Linear Hybrid Cellular Automata of Degree Through 500 by Kevin Cattell and Shujian Zhang. Journal of Electronic Testing: Theory and Applications,6,255-258 (1995) Kluwer Academic Publishers, Boston. provides a list of such maximal length, minimum cost CA’s and will be used an an input to my program

6. Demonstration

7. Thank you