1. GIGABIT ETHERNET DESIGN ECE164.02 - Spring 2004 Group 1 Presentation 5 – Yashar Pirzadeh

2. Week 6 Progress Summary Updated Schematic Design with Recommended Updates Made Initial Board Layout and First Revisions Show Practice Board Transmitter Tests Again Review Optical Link Budget Ordering Parts (including Passives) Updated Gantt Chart

3. Gantt Chart

4. Practice Board TransmitterReceiver

5. Transmitter Assembly (cont.) Back of Board (scraping to eliminate bad grounds)

6. Transmitter Testing 10 dB Attenuation – BER = 0E-9 for 30 seconds

7. Transmitter Testing 10 dB Attenuation – BER = 10E-9 for 30 seconds

8. Transmitter Testing Failure = 50 dB, BER= 10E-7 for 30 seconds

9. Transmitter Testing Bit Error Rate Readings @ 10 dB Attenuation (10E-9)

10. Optical Link Budget Decided on Hamamatsu PD – $18-20 for 1-99 quantity – $6.50 for 10,000+ quantity No luck with VCSEL Passives ordered within next forty-eight hours via credit card to be reimbursed – Budget for these calculated and presented next week

13. Optical Link Budget Considerations VCSEL – Lowest I min is above the lowest I th – Provides enough current to drive VCSEL – Those who cannot drive current eliminated Hamamatsu PD – Picture shows 0.85pF capacitor, 0.010 mA current – Our current is much higher but capacitance worse – Rough extrapolation: it should work – Those who didn’t pass this test eliminated

14. Review of Schematic Changes Minimal: Removed RC Circuit from Receiver Important Considerations: – Tight loops, filters, and power supply location

15. Transmitter Schematic Design

16. Original Receiver Schematic Design

17. Revised Receiver Schematic Design

18. Review of Board Layout Changes Overall – More overall symmetry – 45 degree angles for wires, no reflection of high frequency signals Transmitter – VCSEL straight angle into 3287 through capacitor – Problem: Capacitor about 2mm, only 4 mm space before transmission line issues – Missing portions from Tx schematic included

19. Board Layout Revisions (contd.) Receiver: – Curve the shield around receiver, ground it – Keep power away from high frequency signals

20. Original Board Layout

21. Revised Board Layout

22. Next Week’s Agenda (and beyond) Spring Break Hopefully board is available Begin building board with available parts Nag vendors whose parts are missing Formal Budget Update Gantt Chart

23. THE END Group Members – Russell Cook – Yashar Pirzadeh – James Dezelle