Outline
● VTRx+ front-end module
● Back-end Tx, Rx and TRx modules
● Passives
● System
ATLAS, 14 Nov 2019 [email protected] 2
FPGA
TRX
BackendVTRx+
SERDES
SERDES
SERDES
SERDES
Passives
Front-end Back-end
Useful references from TWEPP-19
P. Moreira
S. Biereigel
S. Kulis L. Olantera
ATLAS, 14 Nov 2019 [email protected] 3
F. Vasey
TWEPP-2019 talks: https://indico.cern.ch/event/799025/timetable/#20190902
1. VTRx+ Front-End Module
● VTRx+ front-end module
● Back-end Tx, Rx modules
● Passives
● System
ATLAS, 14 Nov 2019 [email protected] 4
FPGA
TRX
BackendVTRx+
SERDES
SERDES
SERDES
SERDES
Passives
Reference:
[1] “Versatile Link Plus VTRx+ Specification”, EDMS Document 1719329
[2] “Versatile Link Plus Application note”, EDMS Document 2149674
1.1 VTRx+ Assembly on Host Board
● VTRx+ is mounted upside-down on host board
● Mechanical fixing and fiber strain relief depend on application and environment● The users decide
● Example from CMS OT
ATLAS, 14 Nov 2019 [email protected] 5
1.2 VTRx+ Pigtail
● Pigtail being finalized● Rad hard fibre
● 5 individual fibres in loose tube
● MT termination
● Not dismountable
● Connection with MT Spring Clamp● Dense connectivity at expense of handleability
● Or with MT to MPO adapter● if you have space
ATLAS, 14 Nov 2019 [email protected]
2. Back-End Tx, Rx Modules
● VTRx+ front-end module
● Back-end Tx, Rx modules
● Passives
● System
ATLAS, 14 Nov 2019 [email protected] 7
FPGA
TRX
BackendVTRx+
SERDES
SERDES
SERDES
SERDES
Passives
Reference:
[1] “Versatile Link Plus Backend Array Specification”, EDMS Document 1762899
2.1 Backend Modules with Tightened Specs
● Link power budget is insufficient at end-of-life if using COTS backend components
● VL+ backend modules must have reasonably non-standard specs to close power budget
● Agreement reached with Samtec Inc.● VL+ system must use custom Firefly module at backend
● CERN-specific reference: CERN-B-XXX-XXX-X-X-X-X (see next slide)
● Choice of pigtail length, ribbon type, heatsink type, Tx Rx or Y-module etc.
● Fixed prices irrespective of purchase origin and order volume, 10pcs MOQ
● First 50pcs of each unique configuration (ribbon, heatsink, performance grade, except pigtail length) are more
expensive
● Letter of Authorization from CERN required to link institute to VL+ project
● Prices valid until June 2024, directly through Samtec (not through distributors)
● Expect to release parts for use in VL+ system in Jan-2020
● Preparing list of authorized institutes in the meantime (Q4-2019)
● Electronics coordinator have contacted users to get quantity forecasts (Q4-2019)
● Prices will be communicated to all authorized institutes
● Until end-2019● Users to procure standard Firefly ECUO 14G parts at local market prices
● ECUO and CERN-B parts are pin-compatible
● CERN-B parts provide necessary margin for experiment lifetime and radiation-induced degradation of front-end, but
ECUO parts will work fine for prototypes
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2.2 Firefly CERN-B reference code
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• VL+ trunk cable will be
terminated with female MTP
connectors at backend (TBC)
• Either MTP12 or MTP24
*
References:
[1] Samtec product brief and engineering drawings: FireFly™ CERN-B https://edms.cern.ch/ui/#!master/navigator/document?P:1930058715:1947672741:subDocs
[2] Samtec datasheet: FireFly™ CERN-B, under NDA. Contact [email protected]
*
3. Passives
● VTRx+ front-end module
● Back-end Tx, Rx modules
● Passives
● System
ATLAS, 14 Nov 2019 [email protected] 10
FPGA
TRX
BackendVTRx+
SERDES
SERDES
SERDES
SERDES
Passives
Reference:
[1] “Versatile Link Plus Passive Optical Components Specification”, EDMS Document 1762900
3.1 Cabling plant
● VTRx+ interface (4Tx 1Rx) and Backend interface (12Tx 12Rx) are fixed by VL+ project
● Link length and number of breakpoints are specified by detector● Up to 150m, up to 5 breakpoints
● The shorter the length and the fewer the breakpoints, the better the power margin
● Need aggregation (fan-out) and reshuffling (shuffle) functions in the cabling plant● Keep diversity low and manageable
● Select from «catalogue» three types of cables
● Fanout (naked or rugged)
● Shuffle
● Trunk
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Frozen, see part 2Frozen, see part 1
with two types of fibre
• Standard Rad Tolerant
• Rad Hard
3.2 Design example (1/2)
● CMS Outer Tracker
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PP0 PP1 PPShelf
Naked fan-out Fan-out patch cord Trunk cable
24 24
12
24
PPVTRx+
12
12
PPVTRx+
12
12
PPVTRx+
12
12
PPVTRx+
12
12TO F
RO
NT-E
ND
TR
AN
SCE
IVE
RS
TO B
AC
K-E
ND
TR
AN
SCE
IVE
RS
TRx+
VTRx+ Rad Hard Fibre Standard Rad Tol Fibre
3.2 Design example (2/2)
● CMS ECal
ATLAS, 14 Nov 2019 [email protected] 13
Fan-out patch cord Trunk cable
TO F
RO
NT-E
ND
TR
AN
SCE
IVE
RS
TO B
AC
K-E
ND
TR
AN
SCE
IVE
RS24
12
12
12
12
24
24
24
24
24
12
PP1 PPShelf
24 24
24 24
TRx+
TRx+
TRx+
Shuffle patch cord
PPVTRX+
VTRx+
PP0
Standard Rad Tol Fibre
3.3 Passive Plant: Next Steps
ATLAS, 14 Nov 2019 [email protected] 14
● Rad Hard fibre on order● 800km
● Will eventually have to complement this first order to match total needed length (will require user input !)
● Market Survey for supply of patch cords and assemblies launched (MS-4530/EN/EL)● Fanouts
● Shuffles
● Samples can/must be ordered within MS framework. Users should profit from this opportunity to test their designs
● Expect to freeze portfolio and specs by mid-2020● Preparing list of requirements from all detectors in the meantime (Q4-2019)
● Flavours, parameters, quantities
● Electronics coordinator have contacted detectors to get forecasts (Q4-2019)
● Samples to be ordered in Q1-Q2-2020
● Please participate and fill in survey
● Your last chance to tune the portfolio of parts
● Converge on a shortlist of flavours by Q2-2020
● Expect to launch IT by Q3-2020
● Trunk cables are covered by a more general
Market Survey (MS-4537/EN/EL)
4. System
● VTRx+ front-end module
● Back-end Tx, Rx modules
● Passives
● System
ATLAS, 14 Nov 2019 [email protected] 15
FPGA
TRX
BackendVTRx+
SERDES
SERDES
SERDES
SERDES
Passives
References:
[1] “Versatile Link Plus System Specification”, EDMS Document 1719328
4.1 Power Budget: Two Grades of Links
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● Upstream Power Budget is tight. Depending on link length and radiation environment, extended
grade components must be used.
● Best margin achieved for short links with few breakpoints
4.2 Standard or Extended Grade ?
1. Consider VTRx+ environment
If fluences at VTRx+ position are:a. above standard grade levels > select Extended Grade
b. at/ or below standard grade levels: move to step 2
2. Consider Fibre environmentcalculate Radiation Induced Attenuation (RIA) in fibre (choice of standard and rad hard fibre types)
a. If RIA is below 0.5dB > select Standard Grade
b. If RIA is above 0.5dB > select Extended Grade
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Tolerance level Dose and fluence (1Mev neutron equivalent)
Standard Grade1 MGy
1 x 1014 neutrons/cm2
1 x 1014 hadrons/cm2
Extended Grade1 MGy
1 x 1015 neutrons/cm2
1 x 1015 hadrons/cm2
3. If unsure, contact VL+ team with:- detector ionising radiation map
- fibre route and patch panel locations
- Position of Cold / Warm transition (if applicable)
To determine fibre type(s), calculate total RIA, and select VL+ grade
5 Conclusion
● VL+ gearing towards production
Users to clarify their needs● Electronics Coordinators have distributed three questionnaires for VTRx+, Firefly, passive plant
● Please indicate:
● For Prototypes: desired quantities
● For Production: estimated quantities,flavours, timescales
● Will be an iterative process
● VTRx+ Preprod Q2-2020, prod starting Q4-2020
● Schedule: https://ep-ese.web.cern.ch/content/lpgbt-vl-dcdc-schedule
ATLAS, 14 Nov 2019 [email protected] 18