CMS GBT Use Cases and Requirements Time Constraints 20090505 magnus.hansen@cern.ch

1. CMS GBT Use Cases and Requirements Time Constraints 20090505 magnus.hansen@cern.ch

2. CMS GBT • Specification discussion on the 15/4 2009 • Presentations • CMS HCAL by Chris Tully, Princeton • CMS Tracker by Karl Gill, CERN • CMS DT Muons by Christina Fernandez, CIEMAT • Conclusion • CMS has a reasonably consistent view of the requirements • No contradictory requirements were found M. Hansen, CERN. magnus.hansen@cern.ch

3. CMS Users • CMS HCAL stage 1 Upgrade • GBT is the baseline • GBT Specification as a whole seem adequate • CMS Tracker stage 2 upgrade • GBT (or successor) is likely to be the baseline • CMS Pixels stage 2 upgrade • GBT (or successor) is likely to be the baseline • Potential users stage 2 • ECAL and HCAL End caps • Muons (DT) M. Hansen, CERN. magnus.hansen@cern.ch

4. CMS HCAL • CMS HCAL stage 1 upgrade is highly constraint by the installed infrastructure • Crates (RBX = Readout Boxes) • Installed fibers • Control and readout • Cooling • Power M. Hansen, CERN. magnus.hansen@cern.ch

5. CMS HCAL Front-endDigital Transmitter Board • 72 HB/HE RBX, 4 RM/RBX, 8 Fibers/RM 180 mm 8 Optical Fibers 75 mm Chris Tully

6. CMS HCALGBT Use Cases Off Detector • GBT RxTx for FE control • TTC Relay • Clocks • Synchronous Commands • RM Configuration • GBT Tx, sCCA, QIE • Negligible bandwidth • GBT Tx for Data Transmission • 82 user bits needed • Parallel mode • All “Trigger” Data • 2 bits potentially left for status flags or time markers RBX Control Server sHTR sHTR sHTR RBX On Detector (72 RBXes) 1 GBT RxTx CCM Clock and Control Module 8 GBT Tx RM Readout Module 8 GBT Tx RM Readout Module 8 GBT Tx RM Readout Module Clock Control M. Hansen, CERN. magnus.hansen@cern.ch

7. Total Integrated Neutron FluenceRadiation Levels for Electronics • Similar Radiation Hardness Studies for SiPMs Performed Recently at Neutron Irradiation Facility at Massachusetts General Hospital Chris Tully

8. CMS HCAL Time line • FE design has been modified to give more time for the GBT development • Pre-production need to be available around spring 2011 for tests • Few 100 chips • Production need to be available by Autumn 2011 • 5000 chips • CMS HCAL community is open for suggestions about how to help with the GBT development • Radiation tests etc. M. Hansen, CERN. magnus.hansen@cern.ch

9. CMS Pixel upgrade • Roland and Hans Christian are responsible • Phase 1 upgrade • not foreseen to use GBT • Phase 2 upgrade • It is too early to discuss. The team is busy with the Stage 1 Upgrade M. Hansen, CERN. magnus.hansen@cern.ch

10. CMS Silicon Strip Tracker • Layout is not decided • Requirements are preliminary • What follows is derived from an example layout from D. Abbaneo et. al. (right) • What will not change • Front end Control through GBT • TTC through GBT • Constant predictable latency • in particular for the down link (CR -> Exp) • Negligible error rate • Power budget crucial M. Hansen, CERN. magnus.hansen@cern.ch

11. CMS Silicon Strip TrackerPt layers for track trigger • Based on a set of assumptions • ~1000 GBTs Karl Gill Geoff Hall M. Hansen, CERN. magnus.hansen@cern.ch

12. CMS Silicon Strip TrackerOuter Tracker • Un-sparsified, synchronous binary readout with CBC chip • 100kHz trigger rate • APV-like frame output • Data rate 20MBit/s per CBC • 11k modules, 17M channels • ~1000 GBTs • Expect 1 GBT filled per ‘rod’ of 12 modules in outer barrel Three 4xMUX + copper link drivers each output 80Mbit/s TCS I/O DC-DC shielded micro-twisted pairs I/O DC-DC out 2.5V c c Sensor HV 12x CBC 128ch each wire bonded 20Mbit/s out each Silicon T sensor DCU Sensor with 2x 5cm strips 2x 768 @120um pitch integrated pitch adaptor c c Karl Gill Geoff Hall M. Hansen, CERN. magnus.hansen@cern.ch

13. Summary of TrackerPreliminary Requirements • Sufficient overall bandwidth with low overhead • Will probably need several thousand GBT (excluding pixels) • Need solution to concentrate data onto high bandwidth links • Need low power solution to transmit data to the optical hub (GBTX/VOL) • Considering how to reduce number of links in PT layers • E.g. if we can avoid reading out at 40MHz • Want minimal power for adequate functionality, radiation resistance, reliability • Want minimal material/mass/packaging inside Tracking volume • Move GBTX and VOL outside sensitive volume(s) if possible • Have to measure power/signal integrity on different cables, of different lengths at different bit rates • Weigh up cost/benefit of many Cu- cables versus GBTX nearer front-end. • Require low noise contribution at sensors • Want ease of use/configuration/test of TK system to be kept in mind • Cost and timescales must be inside budget (to be decided) • Will expect more (TK-specific) points to come, plus pixels in due course Karl Gill Geoff Hall

14. Other CMS Users • ECAL and HCAL End caps Stage 2 Upgrade • Studies On-going • Higher effective bandwidth would be welcome • Likely to be around 2000 chips +/- 50% • ECAL Barrel Stage 2 Upgrade • As above but also subject to reliability of the current system • Higher effective bandwidth would be welcomed • Likely to be around 10000 chips M. Hansen, CERN. magnus.hansen@cern.ch

15. Other CMS Users • Muons (DT) • Studies On-going • Radiation levels as CMS HCAL • Schedule as Stage 2 upgrade M. Hansen, CERN. magnus.hansen@cern.ch

16. General Requirements • Front end Control through GBT • Write and Read Access • TTC through GBT • Constant predictable latency • in particular for the down link (CR -> Exp) • Negligible error rate • Power budget is crucial • Maybe less so for ECAL M. Hansen, CERN. magnus.hansen@cern.ch

17. CMS GBT Time Line • 2011 • April • HCAL Pre-production Test ready for test beam in Summer • September • HCAL Production • Tracker Demonstrator tests • 2014 +/- 1 year • Stage 2 production of Electronics • 2018 +/- 2 years • Stage 2 LHC Upgrade M. Hansen, CERN. magnus.hansen@cern.ch