1. ECE 135 Final Presentation The Three … aka Pat Cleary with Kevin Parker & Bryan Chavez April 21 st, 2005 April 21 st, 2005

2. ECE 135 Final Presentation The VCSEL Kings … aka Pat Cleary with Kevin Parker & Bryan Chavez April 21 st, 2005 April 21 st, 2005

3. ECE 135 Final Presentation RIO! … aka Pat Cleary with Kevin Parker & Bryan Chavez April 21 st, 2005 April 21 st, 2005

4. ECE 135 Final Presentation BtrLaytDanNvr Pat Cleary with Kevin Parker & Bryan Chavez April 21 st, 2005 April 21 st, 2005

5. Introduction The Goal: An IEEE 802.3 Standard Gigabit Ethernet Link The Components: Group and time management plan, background research, part selection, optical link budget, circuit design and layout, construction, and troubleshooting.

6. Initial GANTT Chart

7. Group Management Task Task Leader Primary Support Organizational Management PatKevin Optical Link Design KevinBryan Board Layout BryanPat Board Construction BryanPat TestingKevinBryan Report Prep PatKevin

8. Background Research: Overview

9. Background Research: Tx

10. Background Research: Rx

11. Background Research for Four-Corners Analysis Eye safe limit → P max = 1 mW From the 802.3 standard → extinction ratio = 9dB Thus we see that P min = P max *10^(-9/10) P min =.12589 mW

12. VCSEL Four Corner Analysis HFE439x-521 ManufacturerPartI_th (mA) η (mW/mA) I_tot(MAX) (mA) I_tot(MIN) (mA)I_bias (mA)I_mod (mA) Advanced Optical Components (2.5G) SCHFE439x-5410.50.0425.50003.647314.573621.8528 Advanced Optical Components (2.5G) SCHFE439x-5412.50.0427.50005.647316.573621.8528 Advanced Optical Components (2.5G) SCHFE439x-5410.50.166.75001.28684.01845.4632 Advanced Optical Components (2.5G) SCHFE439x-5412.50.168.75003.28686.01845.4632

13. ROSA Selection HFD3180-108 ROSA Part # Min (V/W)Typical (V/W)Max (V/W) Advanced Optical Components (up to 2.5) (LC) HFD3180-108150025003500

14. Optical Link Budget Advanced Optical Components HFE419x-541 with HFD3180-108 ROSA Ith (mA) 1.8 DC Bias of laser (mA) 10.29 Slope Efficiency (mW/mA) 0.125 Modulation Current of Tx (mA) 29.1369 Range of Power Output (mW) 0.12589 - 1.0 Range of Power at Rx (mW) – 7.5 dB Loss.02239 -.17783 Voltage Output Range from ROSA (mV) 55.98 – 444.58 Voltage Input Range for Maxim 3264 (mV) 5 - 1200

15. Additional VCSEL Purchase LC-TOSA 20 Free VCSELs Obtained

16. Introduction to Test Equipment

18. Tx Test Board Construction …

19. … And Immediate Correction Soldered Output Pins in Correct Locations

20. Tx Test Board Performance “Best” Eye Diagram PRBS7 Pattern Troubleshooting Necessary

21. Tx Test Board Troubleshooting Grand Conclusions Outputs and Inputs Reversed If one truly only learns through failure, we’ve learned a LOT already!

22. More Tx Test Board Work

23. Tx Test Board Quality Control Input in Input Output in Output

24. Tx Test Board Performance No attenuation PRBS7 Pattern Still not successful

25. Tx Test Board Conclusions Eye still not well defined Potentiometer has minor effect on performance Conclusion: Board permanently damaged from attempts to drive in reverse direction Result: If continued testing is necessary a new board is needed

26. Completed Tx Test Board – Take 2 ← ← Outputs

27. Tx Test Board Performance 0 dB 70 dB 10 dB ● PRBS7 Pattern ● 3 minute interval ● BER 0 dB)

28. Tx Test Board Performance (Continued) ● 70 db ● AC coupled ● 70 db ● Scaled down using potentiometer

29. Tx Test Board (Take 2) Conclusions Eye diagrams are very well-defined Potentiometer scales the eye dramatically Attenuation has minimal affect on eye Low BER rate suggests quality performance The Three are capable of building a working Tx board!

30. Tx & Rx Schematics Tx Rx

31. TxRx PCB Layout Conservative Agressive

32. Board 1A Construction

33. Board 1A Troubleshooting No Success with Tx or Rx High-Pitched Noise and a Smoking Ferrite Bead… Short Discovered Between Power Supply and Ground (Not from Layout)

34. Board 1B Construction The Three’s Tried-and-True Strategy: Start Over Results: Nothing Breaks During Testing!!!!!

35. Board 1B Troubleshooting Receiver Circuit Functions Perfetto Continuing Issues with Tx

36. Rx Test Setup

37. Rx Results PRBS7 Pattern 9 dB BER < 10^-11 5 minute duration Proper operation verified! Yay

38. Board 1B Transmitter Testing Left and Right Inputs to VCSEL Signals Want to Be Eyes… Not Quite There VCSEL Not Lasing An Attempt at Board 1Γ Tx Also Unsuccessful

39. Aggressive Tx Modifications Soldered all passives super carefully Used a 25k potentiometer to modulate I bias instead of 1k potentiometer Adjusted the VCSEL orientation for forward-biasing Adjusted pot values to safe levels before testing

40. Aggressive Tx Test Setup

41. Aggressive Tx Probing Laser Driver InputsLaser Driver Outputs Data - Data + Data - Data +

42. Aggressive Tx Results LASING!!!! Adjusting I mod and I bias showed improved results

43. Aggressive Tx Results (cont.) Working!!!!!!!!

44. Loopback Testing for Aggressive Design PRBS7 Pattern 7 dB Attenuation Super Yay Too Good to Be True? ….

45. Not This Time! Signal at 8 dB Attenuation is Lower Quality…As Expected BER < 0.0E-10 Removal of an Optical Fiber Produces a Lost Signal Verified Successful Completion of Gigabit Ethernet

46. Final Budget ItemSupplierPart #QtyUnit PriceTotal Amount Ferrite Chip InductorDigikey490-1034-1-ND30 $ 0.12 $ 3.60 Power JackDigikeyCP-002APJCT-ND5 $ 0.81 $ 4.05 POT 1.0kOhmDigikey3296W-102-ND5 $ 2.50 $ 12.50 POT 25kOhmDigikey3296W-253-ND5 $ 2.50 $ 12.50 Resistor 115 OhmDigikey311-115CCT-ND10 $ 0.08 $ 0.80 Resistor 100 OhmDigikey311-100CCT-ND10 $ 0.08 $ 0.80 Resistor 24 OhmDigikeyRR12Q24DCT-ND10 $ 0.15 $ 1.51 Resistor 10 OhmDigikeyRR12Q10DCT-ND10 $ 0.15 $ 1.51 Capacitor 10000 pFDigikeyPCC103BNCT-ND100 $ 0.04 $ 3.66 SMAsJameco901-143-6RFX10 $ 4.20 $ 42.00 2.5 Gbps ROSAAdvanced Optical ComponentsHFD3180-1034 $ 10.00 $ 40.00 2.5 Gbps VCSELAdvanced Optical ComponentsHFE419x-5414 $ 14.50 $ 58.00 PCB Board FabExpress PCB 1 $ 59.00 Shipping and MiscellaneousVarious $ 25.94 Total $ 265.87

47. Bill of Materials ProductVendorItem NumberQtyLarge Qty Price ($)Total Amount ($) POT 25.0K OHMDigikey3296W-253-ND21.0922.184 RES 115 OHMDigikey311-115CCT-ND20.016820.03364 RES 100 OHMDigikey311-100CCT-ND20.016820.03364 RES 24 OHMDigikeyRR12Q24DCT-ND10.02958 RES 10 OHMDigikeyRR12Q10DCT-ND10.02958 CAP 10000 PFDigikeyPCC103BNCT-ND180.018880.33984 CONN PWR JACKDigikeyCP-002APJ-ND10.40338 Ferrite Bead InductorDigikey490-1034-1-ND30.0640.192 VCSELAOCHFE419x-54117.25 ROSAAOCHFD3180-10315.00 Laser Driver ChipMaximMAX328714.00 Limiting Amplifier ChipMaximMAX326414.00 PCB BoardExpress PCB4 Layer Board15.7195 Total $ 29.22

48. Final GANTT

49. The Three – Pratt Worthy!