1. Project GabEECE 135 – Spring 2005Final Presentation Omar Al-Jadda Patrick Crosby Adam Durity Rahmin Sarabi

2. Progress Report • Built final board design • Tested and verified Tx • Tested and verified Rx • Loopback Testing

3. Gantt Chart

4. Project Overview • Research 802.3 Gigabit Ethernet standard • Learn to use the test equipment • Analyze and select optical components to be used • Design and build both an aggressive and a conservative prototype of a 1.25Gbps Optical Gigabit Ethernet PMD

5. Evaluation Board • Tested MAX3287, MAX3266, MAX3264 evaluation boards • Varied attenuation from 0dB down to 70dB • BER = 10^-9 @ 10dB

6. Test Board • Built test board using parts provided • Tested board at 10dB and 30dB • BER = 10^-9 @ 10dB

7. VCSEL • Criteria for selecting VCSEL: • High slope efficiency • Low threshold current • At least 1.25Gbps • We chose the Advanced Optical Components HFE4191-541

8. ROSA • Criteria for selecting ROSA: • High responsivity • High transimpedance • We selected the Advanced Optical Components HFD3180-102

9. GabE Final Schematic - Tx

10. GabE Final Schematic - Rx

11. Conservative Board Designs GabE 1.0 GabE 2.0

12. Aggressive Board Designs GabE 1.0 GabE 2.0

13. Aggressive vs. Conservative • Conservative is designed with one key objective in mind: functionality • Aggressive design achieves LC connector spacing • Aggressive design violates many design rules: asymmetric, long traces

14. GabE 2.0 Conservative Aggressive

15. “Plug ‘n’ Play” Required no additional fiddling Basis for Tx, Rx, and loop-back tests Conservative Board

16. TOSA-ROSA Distance meets LC Specification After build; did not work right away Blew an inductor; smoke etc… Short to ground Separated Tx and Rx Tried to isolate short Aggressive Board

17. Discovered that Tx chip was cause of short! Also destroyed a pin on the LA; used wire jumper Soldered on a new Tx Chip No short to ground Still does not work Aggressive Board

18. Board Building Tips from Ωr • Solder chips on first, carefully, and check the notch! • Solder on smaller passives then larger components, TOSA/ROSA last • Fine tipped soldering iron at 650°F; high gauge solder • Use needle nose pliers to hold in place the SMT component; touch the soldering iron to the solder to form a bead, solder joint

19. Tx Testing - Conservative • Attempted to tune potentiometers, but found that they have little to no effect • Tested Circuit for 10, 20, 30, 50 and 70dB of attenuation

20. Tx Testing - Conservative 10dB High Rbias, High Rmod 10dB High Rbias, Low Rmod 10dB Low Rbias, Low Rmod 10dB Low Rbias, High Rmod

21. Tx Testing - Conservative 10dB Rbias = 500Ω, Rmod = 12.5kΩ

22. Tx Testing - Conservative 30dB Rbias = 500Ω, Rmod = 12.5kΩ

23. Tx Testing - Conservative 70dB Rbias = 500Ω, Rmod = 12.5kΩ

24. Tx Testing - Aggressive 1.0 0dB/810ohm

25. Tx Testing - Aggressive 2.0

26. Aggressive Board

27. Possible Problems • Broken pin on Maxim Chip • Burned Inductor • Burned out traces • Soldering problems

28. Rx Testing - Conservative 0dB 4dB

29. Rx Testing - Conservative 7dB 12dB

30. Loopback - Conservative • Based on Tx Testing, set Rbias and Rmod to 500Ω 12.5k Ω respectively • Tested with 10 and 70dB electrical attenuation and 0 and 9dB optical attenuation

31. Loopback - Conservative 10dB Electrical 0dB Optical Rbias = 500Ω, Rmod = 12.5kΩ

32. Loopback – Conservative 70dB Electrical 9dB Optical Rbias = 500Ω, Rmod = 12.5kΩ

33. Bit Error Rate Tests • Loopback • Electrical: 70dB; Optical: 9dB;BER=10^-10 • Electrical: 10dB; Optical: 9dB;BER=10^-10 • Receiver • Optical: 12dB;BER=10^-10 • Transmitter • Electrical: 70dB;BER=10^-10

34. Financial Budget

35. Bill of Materials

36. Upcoming Week • Complete Final Report

37. Conclusion • ROSA – the solution to the crosstalk problem • ROSA – allows prices to be competative with electrical GbE • Learned skills in project management: Gantt charts, working with vendors, how to work as a team, allocation of time and resources