1. 1 8 � Bit Gray Code Converter Murad Amer Umair Sophie Raymond Vengersammy Advisor: Dr. David Parent May 11, 2005

2. 2 Agenda Abstract Introduction Why 8-bit gray code? Theory of 8-bit gray code encoder Background Information Summary of Results Project (Experimental) Details Results Cost Analysis Conclusions

3. 3 Abstract 8 bit Gray Code Converter converts regular binary number to Gray code numbers Binary ? Gray Operates at a clock frequency of 200 MHz Power: 6mW Area: 265mm x 150mm DFF MS-Latch: Wn = 1.50, 1.65um, Wp = 2.55, 2.70 um SL-Latch: Wn = 1.95, 1.65 um, Wp = 1.65, 2.70 um XOR AOI: Wn = 1.5um, Wp = 2.7um INV: Wn = 1.5um, Wp = 2.7um

4. 4 Introduction Why the Binary Gray Code Converter??? First of all, it applies many of the concepts from the class and lecture (EE-166) BGCC, is applied in many applications This project converts a series of binary numbers to gray code numbers with the use of XOR gates and DFF�s

5. 5 Project Summary Picked an initial load capacitance (Cload) Partitioned the circuit into different propagation delay times according to gate/device requirements Created the schematic, symbol and layout for each type of gate (XOR, MUX-DFF) Limits the amount of error that can occur when several bits change between numbers

6. 6 Conversion Decimal Binary Gray Code 0 0000 0000 1 0001 0001 2 0010 0011 3 0011 0010

7. 7 Project Details Binary to Gray Uniform cell heights of 30 �m 7 XOR gates 16 Mux based D-Flip Flops

8. 8 Longest Path Calculations

9. 9 Schematic (DFF)

10. 10 Layout ( DFF)

11. 11 Simulations (DFF)

12. 12 Schematic (XOR)

13. 13 Layout ( XOR)

14. 14 Gray Code Schematic

15. 15 Gray Code Layout

16. 16 Verification

17. 17 Gray Code Simulation

18. 18 Cost Analysis We Spent Many Hours on this Project Verifying logic = 10 hrs Verifying timing = 30 hrs Layout = 25 hrs Post extracted timing = 5 hrs

19. 19 Lessons Learned START EARLY! FOCUS in class START EARLY!! Utilize other students in the class START EARLY!!! Work as a TEAM efficiently START EARLY!!!!

20. 20 Summary This Project explained the Fundamentals of EE-166 Taught us the Ins - and - Outs of basic Design Less Power Used, Less Area Used Met Specifications

21. 21 Acknowledgements Thanks to our families for putting up with us for not being home. Thanks to Cadence Design Systems for the VLSI lab Thanks to Synopsys for Software donation Dr. David Parent Thanks to the janitors/security for letting us spend late hours in the labs.