TTC system for FP420 reference timing

1
TTC system for FP420 reference timing?
TTC Timing Trigger Control
The reference time, common signal to E and W
detectors is as important as the detectors
themselves. Want lt 5 ps E-W jitter
Sophie Baron (PH-ESS) Mike Albrow (Fermilab)
2
Proposed Scheme for Reference Time transmission
Not really needed

• Bunch Clock and Orbit to be transmitted
• Level of radiation ?? . We will need
  calculation of this. (Results here)
• Clock monitoring between the 2 signals
• Goal 5 ps rms jitter skew between the clocks in
  W and E

3
Existing system

• The TTC system
• Rad-hard chips
• Monitoring the phase between 2 optical signals
• Various transmission schemes used by the TTC
  system
• Typical jitter values

4
TTC system in one slide
This is standard equipment provided by LHC for
experiments

• Transmission of
• Timing of the LHC from the RF source to the
  experiments
• LHC Bunch Clock (40.078xx MHz)
• Revolution Frequency (11.245x kHz)
• Then combined inside the experiments with
• Trigger and Control signals
• Used by front-end electronics and readout systems
• Using single optical fibres

• and a lot of various components and modules

5
Radiation hard components

• TTCrx
• 50ps rms
• The TTCrx is now fabricated in the radiation-hard
  DMILL technology, which completely eliminates the
  possibility of a single-event latch-up, and
  should show a high immunity to single-event upset
  (SEU).
• Tested up to 8 Mrad (X-Rays) and 5 x1013
  n/cm2 (Neutrons)
• QPLL
• 10-15ps rms
• Tested up to 10Mrad (Co-60 ?) 3 1015 n/cm2
• TRR receiver
• Optical receiver from Truelight (Taiwan) selected
  for most of the TTC designs
• Tested with the TTCrx at the same doses.
• OK if the optical power level stays above -20dBm
  (0.1mW)
• Optical Fibers
• sensitive to radiation (attenuation increases
  with the dose)
• Special fibres validated for ATLAS and CMS at
  high radiation levels (1014-1015 n cm-2 and total
  dose of 100 to 300 kGy)
• Radiation hardness of multi-mode optical fibres
  for the ATLAS detector readout (June 1999,DG
  Charlton et all)

Phased locked loop voltage controlled Quartz
crystal oscillator (VCXO)
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Transmission Schemes

• Encoded
• TTC inside the experiments (based on aTTCrx chip)
• Advantage Allows to encode the orbit signal (and
  control frames) to the 40.078MHz
• Drawback jitter increases with the quantities of
  encoded data
• QPLL added to reduce the jitter of the recovered
  clock down to 10-15ps rms
• We choose the alternative, better
  resolution
• Parallel
• TTC backbone system
• Orbit and clock on separate fibres
• Advantage very low jitter after the
  opto-electrical conversion (lt10ps) without using
  the QPLL

7
Parallel Scheme

• Clock and orbit on parallel fibres
• RF signal transmission scheme

Picture RF_Tx_D
Picture RF_Rx_D
Tx Board
Rx Board

• Laser Types
• OCP03 300
• OCP Tx 24 600

• Photodiode Types
• OCP Rx 03 230
• OCP Rx 24 300
• TRR 8 CHF!

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Typical Jitter values Parallel Scheme
C1
OCP Tx 03
C3
C2
OCP Rx 03 fanout ECL driver
OCP Rx 03 fanout ECL driver
C1/C3 11.4ps
C2/C3 4.0ps
C1/C2 11.5ps
Lecroy Wavepro 7100 1GHz
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Proposed Scheme for Reference Time transmission
WILL DO
Not really needed

• Bunch Clock and Orbit to be transmitted
• Level of radiation ?? . We will need
  calculation of this. (Results here)
• Clock monitoring between the 2 signals
• Goal 5 ps rms jitter skew between the clocks in
  W and E

10
Conclusions There is
a Reference time signal solution with East-West
rms lt 5 ps. Proposal will be written for TDR by
Sophie Baron in consultation with MGA ( anyone
interested). We should ask for this to be
provided by CERN (will FP420 have to pay
something? If so, modest.)
11

• 6th Workshop
• Small x and Diffractive Physics
• 28-31 March 2007
• Fermi National Accelerator Laboratory, Batavia,
  Illinois, USA
• Just preceding FP420 April 2-3 UTA (Texas)
• The purpose of the Workshop is to present and
  discuss experimental,phenomenological
• and theoretical progress in high energy
  diffractive interactions.
• Results from the Tevatron, HERA and RHIC covering
  small-xphenomena in the nucleon and nuclei,
  large rapidity gaps, as well asrelevant cosmic
  ray interactions will be presented. Attention
  will be paidto the possibilities of measuring
  exclusive Higgs bosons, vector bosonpairs, and
  Beyond Standard Model phenomena at the LHC with
  forward protonspectrometers."
• Organizing Committee M.G.Albrow(FNAL),J.Bartels(
  Univ.Hamburg), A.Brandt(UTA),
• A.DeRoeck(CERN), K.Eggert(CERN),K.Goulianos(Rockef
  eller Univ.), W.Guryn(BNL),
• J.Huston(MSU), L.McLerran(BNL),
  R.Orava(Helsinki),J.Repond(ANL),C.Royon(Saclay),
• M.Ruspa(Torino), C.Sazama(FNAL) Co-chairs
• Contact Information C.Sazama, P.O.Box 500, MS
  113, Batavia IL 60510
• tel [phone], email sazama_at_fnal.gov
• need this from Christophe http//conferences.fn
  al.gov/smallx07