1 / 12

TTC system for FP420 reference timing?

TTC system for FP420 reference timing?. TTC = Timing Trigger Control. Sophie Baron (PH-ESS). FP420 requirements for timing transmission. Bunch Clock and Orbit(?) to be transmitted Level of radiations = ?? Clock monitoring between the 2 signals

jun
Download Presentation

TTC system for FP420 reference timing?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. TTC system for FP420 reference timing? TTC = Timing Trigger Control Sophie Baron (PH-ESS) FP420 Collaboration meeting, Sept. 2006

  2. FP420 requirements for timing transmission • Bunch Clock and Orbit(?) to be transmitted • Level of radiations = ?? • Clock monitoring between the 2 signals • 10 ps rms jitter skew between the clocks in W and E FP420 Collaboration meeting, Sept. 2006

  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 FP420 Collaboration meeting, Sept. 2006

  4. TTC system in one slide …and a lot of various components and modules… 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 … • TriggerandControlsignals • Used by front-end electronics and readout systems …Using single optical fibres… FP420 Collaboration meeting, Sept. 2006

  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 γ) + 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 radiations (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) FP420 Collaboration meeting, Sept. 2006

  6. Clock differences Monitoring? Comparator control • Phase shift with temperature: • Typical value: shift of 25ps/degC/km • FP420 => 12ps/C per side if 420m on each side • Limit of the measurement: • The jitter between the W and E zones can not be monitored, as it is manly generated by the electronics doing the optical to electrical conversion • The measurement will only concern the phase shift between the 2 segments FP420 Collaboration meeting, Sept. 2006

  7. 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 • Parallel • TTC backbone system • Orbit and clock on separate fibres • Advantage: very low jitter after the opto-electrical conversion (10ps) without using the QPLL FP420 Collaboration meeting, Sept. 2006

  8. Encoded Scheme [1] B* A 40MHz Clock TDM Encoder A B A B A B A B A B + BPM 25ns A Orbit B* (Idle) 0 0 0 1 0 1 1 1 • Used to transmit Timing, Trigger and Control inside the experiments • Serial transmission • 2 Channels are transmitted • A Channel: • Broadcasting Orbit (or L1a in experiments) • Low latency • Time critical signals • B Channel: • Framed & formatted commands and data (Hamming) • Broadcast or individually addressed • Internally used in the experiments • A & B are Time Division Multiplexed • BiPhase Mark encoding is used at 160.316Mbaud: balanced signal FP420 Collaboration meeting, Sept. 2006

  9. Encoded Scheme [2] 50ps rms cy2cy Decoded CH. A Recovered Clock Clock TTCrx TRR QPLL Decoded CH. B Encoder & laser tx Photodiode, decoder & clock recovery Encoded Clock, A, B TTCrq CH. A (pulse, Orbit or trigger) CH. B (serial data frame) 40MHz Clock TTCex 15ps rms cy2cy FP420 Collaboration meeting, Sept. 2006

  10. Parallel Scheme Clock and orbit on parallel fibres RF signal transmission scheme Laser Types OCP03: 300 $ OCP Tx 24: 600 $ Picture RF_Tx_D Picture RF_Rx_D Tx Board Rx Board • Photodiode Types • OCP Rx 03: 230 $ • OCP Rx 24: 300 $ • TRR: 8 CHF! FP420 Collaboration meeting, Sept. 2006

  11. Typical Jitter values – Parallel Scheme [1] Comparator control C1 OCP Tx 03 C3 C2 TRR-1B43 + fanout +ECL driver TRR-1B43 + fanout +ECL driver C1/C3 12.4ps C2/C3 6.5ps C1/C2 12.4ps Lecroy Wavepro 7100 1GHz FP420 Collaboration meeting, Sept. 2006

  12. Typical Jitter values – Parallel Scheme [2] Comparator control 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 FP420 Collaboration meeting, Sept. 2006

More Related