Feasibility Study for: IEEE GbE Electrical Backplane / Copper Cabling Study Group. Fort Lauderdale, FLA. Vittal Balasubramanian

Transcription

1 Feasibility Study for: IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group Fort Lauderdale, FLA Vittal Balasubramanian Signal Integrity Team January

2 Purpose To show the possible reach that can be obtained at Gbps with low loss boards and a new FCI Connector Concept (CC) To show the performance of a short link ( cm) and a long link (7 cm) consisting of a line card, a switch card, a backplane and two connectors compared to an IEEE 8.ap spec extrapolated to Gbps ICN requirements shown here are commensurate with the OIF CEI- G-LR spec (Nov 6, revision of OIF8.6.) Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

3 Typical Backplane Channel Loss Source: GbE Electrical Backplane / Cu Cabling Call-For-Interest Presentation.7 m of traces on Backplane and two line cards (excluding connector length) Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

4 Simulation Settings The FCI Connector Concept (CC) D geometry was solved using CST MWS 9.7 Two link cases simulated :. m :.7 m 8 pairs simulated ( Tx and Rx) Frequency range: to GHz Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

5 Link Description LINE CARD (SIDE A): Length = cm to cm Dk/Df =.6 /. Trace width = 6 mil Trace thickness = 7. um BACKPLANE: Length = cm to cm Dk/Df =. /.8 Trace width = 6 mil Trace thickness = 7. um SWITCH CARD (SIDE B) Length = cm to cm Dk/Df =.6 /. Trace width = 6 mil Trace thickness = 7. um LINK Length on line card Length on backplane Length on switch card Total trace length cm cm cm cm cm cm cm 7 cm Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

6 TX/RX Configuration SIDE A LINE CARD SIDE B SWITCH CARD L T- R- L K R+ R8- T8- K T+ J T8+ J R8+ I T- R- I H R+ T7- R7- H T+ G R7+ G T7+ F R- T- F E T+ T6- R6- E R+ D R6+ D T6+ C R- T- C B T+ R- T- B R+ A T+ A R+ Simulated for columns & Note: Wiring pattern chosen based on optimization for lowest ICN at Gbps Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN 6

7 Link Description: Daughter Cards Board thickness =. mm 6 layers. mm S S S S S S6 ROUTING AB: Layer S DE: Layer S GH: Layer S JK: Layer S BC: Layer S EF: Layer S HI: Layer S KL: Layer S With back-drilling Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN 7

8 Link Description: Backplane Board thickness = 6. mm layers 6. mm S S S S S S6 S7 S8 ROUTING AB: Layer S DE: Layer S GH: Layer S JK: Layer S BC: Layer S EF: Layer S HI: Layer S KL: Layer S With back-drilling Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN 8

9 CC Footprint DC & BP Signal vias: Drilled hole =. mm Finished hole =. mm Pad size =.7 mm Ground vias: Drilled hole =.6 mm Finished hole =. mm Pad size =.8 mm Antipad:. x. mm Via models solved with VisualViaCad (FCI proprietary Quasi-Static solver) Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN 9

10 Gb/s - CC - AB(A) TO AB(B) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN = mv - ICN =. mv ATT at.896 GHz [db] Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

11 Gb/s - CC - DE(A) TO DE(B) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN = 7.7 mv - ICN =.99 mv ATT at.896 GHz [db] ILD excursions on the short link are due to impedance mismatches in the connector footprint and could be addressed in many ways. One of them being reducing the diameter and/or length of the press-fit pin Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

12 Gb/s - CC - GH(B) TO GH(A) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN = 9.98 mv - ICN =.6 mv ATT at.896 GHz [db] Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

13 Gb/s - CC - JK(B) TO JK(A) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN =.766 mv - ICN =. mv ATT at.896 GHz [db] Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

14 Gb/s - CC - BC6(A) TO BC6(B) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN = 7.86 mv - ICN =.9 mv ATT at.896 GHz [db] Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

15 Gb/s - CC - EF6(B) TO EF6(A) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN = 9. mv - ICN =.87 mv ATT at.896 GHz [db] Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN

16 Gb/s - CC - HI6(B) TO HI6(A) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN =.99 mv - ICN =.679 mv ATT at.896 GHz [db] ILD excursions on the short link are due to impedance mismatches in the connector footprint and could be addressed in many ways. One of them being reducing the diameter and/or length of the press-fit pin Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN 6

17 Gb/s - CC - KL6(A) TO KL6(B) INSERTION LOSS - ATTENUATION INSERTION LOSS DEVIATION RETURN LOSS - - Insertion loss [db] Insertion loss deviation [db] - - Return loss [db] ICN [mv, RMS] INTEGRATED CROSS-TALK NOISE - ICN =.6896 mv - ICN =.9 mv ATT at.896 GHz [db] Feasibility Study for IEEE 8. GbE Electrical Backplane / Copper Cabling Study Group JAN 7