1. The Versatile Link Feasibility Demonstration (Project phase II)
Francois Vasey, on behalf of the Versatile Link Team

2. Versatile Link Project
Joint Project Proposal submitted to ATLAS & CMS upgrade steering groups in 2007 and endorsed in 2008
Project Kick-off: April 2008
Phase I: Proof of Concept (18mo)
Phase II: Feasibility Study (18mo)
Phase II: Consolidation (6mo)
Phase III: Pre-production readiness (18mo)
Optical Physical layer linking front- to back-end
Bidirectional, ~5Gbps
Versatile
Multimode (850nm) and Singlemode (1310nm) versions
Point to Point and Point to Multipoint architectures
Front-end pluggable module
On-Detector
Custom Electronics & Packaging
Radiation Hard
Off-Detector
Commercial Off-The-Shelf (COTS)
Custom Protocol
29 Sep 2011
on behalf of Versatile Link team

3. francois.vasey@cern.ch on behalf of Versatile Link team
VL Versatility
Front-End VTRx
Fibre
Back-End TRx
EE laser, 1310nm SM
LR-SFP+ TRx
VCSEL, 1310nm
SNAP12’like Rx
InGaAs PIN, 1310nm
Opto Engine Rx
VCSEL, 850nm MM
SR-SFP+ TRx
GaAs PIN, 850nm
SNAP12’like Tx,Rx, TRx
InGaAs PIN, 850nm
Opto Engine Tx, Rx, TRx
29 Sep 2011
on behalf of Versatile Link team

4. VL Options and feasibility in March 2011
Front-End VTRx
Fibre
Back-End TRx
EE laser, 1310nm
GBLD Drive current limitation SM
LR-SFP+ TRx
VCSEL, 1310nm
Check GBLD compliance Voltage
SNAP12’like Rx
SM Tx not (yet) available
InGaAs PIN, 1310nm
Opto Engine Rx
VCSEL, 850nm MM
RIA in cold at low dose rate
SR-SFP+ TRx
Tx OMA to meet power budget
GaAs PIN, 850nm
Responsivity drop under irradiation
SNAP12’like Tx,Rx, TRx
InGaAs PIN, 850nm
Responsivity/Leakage to be confirmed
Opto Engine Tx, Rx, TRx
29 Sep 2011
on behalf of Versatile Link team

5. Consolidation Phase: March-Sept 2011
Consolidation Phase launched to address following issues:
Power budget
In-detector fibre: Radiation Induced Attenuation in the cold
Front-end Pin: Radiation Induced Responsivity Drop
Back-end Tx: High OMA requirement downstream
VTRx feasibility
GBLD
availability
VCSEL compliance voltage
Edge Emitter drive current
Full prototype demonstration
High Density Back-End Components Survey 1 2 3 4
29 Sep 2011
on behalf of Versatile Link team

6. Issue 1: Radiation-Induced Attenuation in the cold
Optical Fibres will operate well under radiation in the cold
See D. Hall’s talk, B5b
A fibre is qualified if its total RIA is less than 1 dB SM SM
Dose Rate:
0.66 kGy(Si)/hr MM MM
D. Hall et al
29 Sep 2011
on behalf of Versatile Link team

7. Issue 2: (1/2) Pin Radiation Induced Responsivity drop
Calorimeter
Tracker
J. Troska et al
29 Sep 2011
on behalf of Versatile Link team

8. Issue 2: (2/2) Pin Radiation Induced Responsivity drop
Only an issue at high fluences for MM GaAs Pin diodes
Calorimeter grade Versatile Link
If MM
use standard GaAs MM pins
use COTS transmitter at backend
Tracker grade Versatile Link
If SM
use InGaAs Pin
use «COTS» transmitter (LR) at backend
use InGaAs Pin with upgraded transmitter at backend
29 Sep 2011
on behalf of Versatile Link team

9. Versatile Link System Specification
Four Versatile Link flavours defined
Power budget specified with margin for all flavours
Jitter budget adapted from FC 4G standard
Specs available as EDMS document CERN
Fibre Type
Radiation Tolerance Grade
Calorimeter-grade Tracker-grade
10 kGy, 5x1014 n/cm kGy, 2x1015 n/cm2,1x1015 h/cm2 SM MM
29 Sep 2011
on behalf of Versatile Link team

10. Back End components
Can be COTS, except in Tracker grade MM(850nm) link
Several SFP+ TRx modules successfully evaluated
Parallel optics under evaluation
See A. Prosser’s poster (optoelectronics and links)
Fibre Type
Radiation Tolerance Grade
Calorimeter-grade Tracker-grade
10 kGy, 5x1014 n/cm kGy, 2x1015 n/cm2,1x1015 h/cm2 SM
Min Tx OMA: -5.2dBm
Min Tx OMA: -3.6dBm MM
Min Tx OMA: -3.2dBm
Min Tx OMA: -1.6dBm
29 Sep 2011
on behalf of Versatile Link team

11. francois.vasey@cern.ch on behalf of Versatile Link team
COTS SM SFP+ TRx
Measurement Norm
OMA dBm*
Rx Sensitivity dBm
Ext. Ratio 3.0 dB
Tx. Eye Opening 60% of OMA
Tx Rise Time 70 ps
Tx Fall Time 70 ps
Tx Total Jitter of UI
Tx Deterministic Jitter 0.12 of UI
Rx Total Jitter of UI
Rx Deterministic Jitter 0.14 of UI
A. Prosser et al.
* Tracker Grade Version
29 Sep 2011
on behalf of Versatile Link team

12. MM Parallel Device Testing at 5 Gbps
A. Prosser et al.
29 Sep 2011
on behalf of Versatile Link team

13. Issue 3: GBLD ASIC availability
GBLD-V3 assembled on VTRx:
Functional (marginally, with Zinput matching circuit)
Drives VCSEL and Edge Emitter
See C. Soos’ talk, B5b
GBLD-V4 redesign
To be submitted in Nov 2011
See G. Mazza’s poster (optoelectronics and links)
29 Sep 2011
on behalf of Versatile Link team

14. francois.vasey@cern.ch on behalf of Versatile Link team
GBLD V3 + SM EEL
C. Soos et al.
29 Sep 2011
on behalf of Versatile Link team

15. francois.vasey@cern.ch on behalf of Versatile Link team
GBLD V3 + MM VCSEL
C. Soos et al.
29 Sep 2011
on behalf of Versatile Link team

16. Issue 4: (1/2) VTRx prototype demonstration
Optical connector interface designed and fabricated using rapid 3D prototyping
Different materials
Different designs
Several VTRx prototype versions built and tested
SM, MM
GBLD, TI-ONET LDD
See C. Soos’ talk, B5b
29 Sep 2011
on behalf of Versatile Link team

17. francois.vasey@cern.ch on behalf of Versatile Link team
Issue 4: (2/2) VTRx prototype demonstration
SEU test of complete assembly
See J. Troska’s poster (optoelectronics and links)
In-system performance being evaluated
A. Xiang, SMU
Interfaces to higher system level being prepared
See P. Vichoudis’ talk, B5b
29 Sep 2011
on behalf of Versatile Link team

18. SEU Test of VTRx prototype
VTx
VRx MM SM
J. Troska et al.
29 Sep 2011
on behalf of Versatile Link team

19. In System Performance of VTRx
RT vs -30/+70
Uplink
Downlink
MM uplink
SM downlink
PRELIMINARY
A. Xiang et al.
29 Sep 2011
on behalf of Versatile Link team

20. Versatile Link Feasibility Demonstrated
VL project status, Sep 2011
Front-End VTRx
Fibre
Back-End TRx
EE laser, 1310nm
GBLD Drive current OK SM
LR-SFP+ TRx
VCSEL, 1310nm
GBLD compliance Voltage OK
Board-edge Rx
SM Tx not (yet) available
InGaAs PIN, 1310nm
Opto Engine Rx
VCSEL, 850nm MM
RIA in cold at low dose rate OK
SR-SFP+ TRx
Tx OMA to meet Tk power budget
GaAs PIN, 850nm
Responsivity drop: Calo grade OK
Board-edge Tx,Rx, TRx
InGaAs PIN, 850nm
Assembly to be confirmed: Tk grade
Opto Engine Tx, Rx, TRx TK
grade
Versatile Link Feasibility Demonstrated
Calo
& Tk
grade
29 Sep 2011
on behalf of Versatile Link team

21. Fallbacks for Tk-grade back-end transmitters
What if SM array transmitters cannot be found?
Use single channel transmitter in broadcast mode
Must foresee addressability at GBLD, GBT or GBT-SCA level
SM PLC splitters tested and found to be radiation resistant
What if MM high power transmitters cannot be found?
Select SM
We believe SM and MM parallel optics will be found
oRx
oTx
splitter
oRx
oTx
oRx
oTx
oTx
oRx
oRx
oRx
oTx
oRx
oTx
29 Sep 2011
on behalf of Versatile Link team

22. Towards Versatile Link Project Phase III
Common R&D
VL Phase II
Detector specific R&D 2020
Generic Tendering 2015
(depending on users commitment)
VL Phase III
5G low power VTRx for Tk application
Low power VCSEL driver, small footprint package
10G opto engine VnTx for Calo application
Driver array, VCSEL array, package
TOSA (MM)
ROSA (GaAs 850)
Fibre (MM)
TRx (MM-calo)
Opto-engine (MM-calo)
29 Sep 2011
on behalf of Versatile Link team

23. francois.vasey@cern.ch on behalf of Versatile Link team
Conclusion
Versatile Link feasibility demonstrated
Detailed specifications
Components shortlist
Irradiation test results
VTRx prototype
System demonstrators
Cost book
Versatile Link phase III defined
Completion of generic R&D
Launch of detector specific R&D for 2020 applications
Launch of generic tendering for 2015 applications, if commitment
29 Sep 2011
on behalf of Versatile Link team

24. francois.vasey@cern.ch on behalf of Versatile Link team
Credits
CERN
Jan Troska, Vincent Bobillier, Spyros Papadopoulos, Christophe Sigaud, Csaba Soos, Pavel Stejskal, Sarah Storey, et al.
Fermilab
Alan Prosser, Mark Bowden, John Chramowicz, et al.
Oxford
Todd Huffman, David Hall, Nick Ryder, Tony Weidberg, et al.
Southern Methodist University
Annie Xiang, Andie Liu, Kent Liu, Jingbo Ye, et al.
29 Sep 2011
on behalf of Versatile Link team

25. Downstream Versatile Link Power Budget
Tracker-grade back-end transmit power must be boosted to compensate radiation penalties
Calorimeter-grade power budget compatible with COTS component specs
29 Sep 2011
on behalf of Versatile Link team