1. 23 April, 2008Gabriele Giovanetti – INFN - LNS1 New electronics architecture in NEMO – phase 2. Gabriele Giovanetti – INFN – LNS NEMO Phase 1: 4 floor tower off Catania Harbour NEMO Phase 1: 4 floor tower off Catania Harbour NEMO Phase 2: 16 floor tower off Capo Passero NEMO Phase 2: 16 floor tower off Capo Passero

2. 2 Phase 1 vs phase 2 tower NEMO phase 2 (16 floors) NEMO phase 2 (16 floors) 14 “standard” floors: same electronics of phase 1 with some new items 14 “standard” floors: same electronics of phase 1 with some new items 2 “experimental” floors: new electronics 2 “experimental” floors: new electronics NEMO phase 1 (4 floors)

3. 23 April, 20083 Floor electronics in phase 1 Current floor electronics arrangement: Current floor electronics arrangement:  1 FCMB  4 FEM  640 Mb/s optical link between underwater and onshore board  PCI bridge from onshore FCM to FCMI Off-shore Floor On-shore FEB#0FEB#1FEB#2FEB#3 3 FCMI 2 FEM#2FEM#3 FEM#0FEM#1 1 Optical Link FCM GbE New items in nemo phase 2 “standard” floors New items in nemo phase 2 “standard” floors  Real-time link with hydrophones AES3 standard audio format (24 bit @ 192 kHz sampling)  DC floor power module  Calibration board inside OM

4. 23 April, 2008Gabriele Giovanetti – INFN - LNS4 Phase 1: FEM board Current arrangement: FEM features Current arrangement: FEM features  PMT data acquisition Low-pass filtering of signal Low-pass filtering of signal Nonlinear analog signal compression (equivalent dynamics: 13 bit) Nonlinear analog signal compression (equivalent dynamics: 13 bit) 2 x 100MHz 8 bit ADC, achieving a 200 MHz sampling frequency → 1.6 Gb/s for continuous sampling 2 x 100MHz 8 bit ADC, achieving a 200 MHz sampling frequency → 1.6 Gb/s for continuous sampling 80 kHz measured hit rate and 120 bits per hit (zero skipping) → 10Mb/s average data rate 80 kHz measured hit rate and 120 bits per hit (zero skipping) → 10Mb/s average data rate 3 LVDS lines (twisted pairs) 3 LVDS lines (twisted pairs)  20 Mb/s line for physics data  5 Mb/s line for clock  5 Mb/s line for control data  PMT high voltage management  Environmental parameters monitoring NEMO Phase 1 experience has shown that data rate of 20 Mb/s is enough to send over- threshold hits

5. 23 April, 2008Gabriele Giovanetti – INFN - LNS5 Phase 1: FCM board Current arrangement: FCMB features Current arrangement: FCMB features  Optical link with on-shore system.  Clock recovering from optical link serial stream  Clock distribution to all peripherals, including FEM boards  Collecting physics data from front end and sending them onshore  Collecting environmental data from peripherals, including FEMs and Slow Control board.  AES3 I/F with hydrophones sampling board  Communicate with calibration board.

6. 23 April, 2008Gabriele Giovanetti – INFN - LNS6 Gathering floor electronic devices Integration between mechanics and electronics is a time and work consuming task. Maximizing electronic devices gathering on each floor would make integration easier. Integration between mechanics and electronics is a time and work consuming task. Maximizing electronic devices gathering on each floor would make integration easier. Moreover, it could minimize power dissipation and reduce mechanical connection. Moreover, it could minimize power dissipation and reduce mechanical connection. Two options are possible for this purpose: Two options are possible for this purpose: A - All electronics inside Optical Modules B - All electronics inside FCM: → One board to perform 4 FEMs and one FCM tasks

7. 23 April, 2008Gabriele Giovanetti – INFN - LNS7 No electronics inside O.M.? Optimum solution Optimum solution Only passive electronics inside optical modules. Only passive electronics inside optical modules. FCMB does all the work for PMT management simply with enough copper links FCMB does all the work for PMT management simply with enough copper links Difficult monitoring of environmental parameters Some electronics could be needed anyway (PMT HV, Time Calibration board) Realistic solution Realistic solution Some electronics inside OMs Some electronics inside OMs Line driver Line driver Simple control board (PMT HV, environment, slow serial link with FCMB) Simple control board (PMT HV, environment, slow serial link with FCMB) Time calibration board Time calibration board

8. 23 April, 2008Gabriele Giovanetti – INFN - LNS8 New FCM board requirements New FCM offshore board features New FCM offshore board features  4x 14 bit 200 MHz low power ADCs 14 bit dynamics allow us to remove compression 14 bit dynamics allow us to remove compression  Backbone I/F remains unchanged  Proprietary mezzanine I/F unchanged  Peripherals I/F unchanged Hydrophones Hydrophones Time calibration Time calibration Slow control Slow control

9. 23 April, 2008Gabriele Giovanetti – INFN - LNS9 New FCMB offshore block diagram

10. 23 April, 2008Gabriele Giovanetti – INFN - LNS10 Floor throughput needs Floor data rate with 14 bit sampling Floor data rate with 14 bit sampling  Continuous sampling: 4 x 14bit @ 200MHz → 11.2 Gb/s  Slow control bandwidth: 5 Mb/s  Optical link available payload: 640 Mb/s per floor NEMO phase 1 shows that 20 Mb/s for each PMT is enough for over-threshold hits 8 bit sampling @ 200 MHz. NEMO phase 1 shows that 20 Mb/s for each PMT is enough for over-threshold hits 8 bit sampling @ 200 MHz.  Expected data rate for over-threshold hits (14 bit @ 200 MHz sampling) : ≤ 4 x 35 Mb/s = 140 Mb/s  Lower data rate possible with 8 bit sampling of s.p.e. hits Benefit: no constraints on data flow from OM to FCM (was 20 Mb/s in current arrangement) Benefit: no constraints on data flow from OM to FCM (was 20 Mb/s in current arrangement)

11. 23 April, 2008Gabriele Giovanetti – INFN - LNS11 PMT analog signal transmission PMT analog signal transmission from OM to FCM PMT analog signal transmission from OM to FCM  Current arrangement sees a ~8m distance between OM and FCM  This distance could change in the future, but won’t exceed ~10m.  For such distances analog signal transmission is not a challenging problem.  For longer distances a line driver that matches cable impedance could be needed between PMT and cable.  A simple copper link between PMT output and FCMB could be imagined. Mismatch between PMT output and cable impedance would only affect low-pass filter design.

12. 23 April, 2008Gabriele Giovanetti – INFN - LNS12 Onshore FCM board New FCMB onshore features New FCMB onshore features  FCM board will mantain same optical link (10 Gb/s)  Bridge towards FCMI will support PCI express bridge (up to 2 Gb/s per line)