PS/SPD Electronics Installation and Commissioning 17 July 2007 Valentin Niess On behalf of LPC Clermont

2 PS/SPD FEB Production Status  Production & Tests running smoothly now: 16 PS/SPD FEB/week (Thanks to dedicated test team! - Catherine & Christophe - ) - No more PCB issues : 2/7 boards in preserie II - PGA programmed before implantation / Delayed production But … No more PGA problems !!! ( 6/15 boards PGA issues in preserie )  Potential shortcut spotted with RJ45 A2 connectors shielding  back manufacturer ( Hitachi ) 12 % RJ 45 A2 connector C side threshold Pres. Lot 1 Lot 2 Lot 3Lot 4 16/07 23/07 11/0722/06 Pres.Lot 1 Lot 2 Lot 3Lot 4 16/0723/0711/07 22/06 Valid PRS FEB status Target is to equip C side before end of July / installation ‘on flight’ 10 FEBs with A2 to be fixed Faillure Rate ( % ) # PRS FEB

3 PRS Electronics Installation Status  All VFE previously installed & cabled April-May All tested and left OK Problems: Dead contacts (RJ45 analogic signal/clock) ~1/5 boards VFE not powered / Low Voltage ~1/50 boards Solved by re-plugging RJ45 or VFE power cable Notice: RJ45 dead contact occur both on FE and VFE side  2 FE Half crates installed end of June: PRS0 ( SM1 ) PRS3 ( SM4 ) but A2 connector issue  de-cabled / re-cabling What did we learn from this ? + PhoTo

4 FE Installation: 1st Trial  Cabling rate: 1 crate / day … and … Its ‘feasible’ to get boards out after / but in packs of 3-4 …  Traveller Test: Short serie of production Tests  ensure travel was good No surprises!  Hunt RJ45 dead contacts with noise measurements ( VFE noise rules ) With VFE Without VFE inf(  VFE ) > sup(  FE ) Dead contacts: easy to see however repairing a contact can endommage another one … Let’s cross our fingers that the procedure always converges … Final check required when ‘closing the box’ No excess noise with HV up to 650 V

5 VFE POWER ISSUES  3 out of 14 VFE tested end of June seemed to be badly powered : They were left functionnal in may !!!  SM1 bottom box opened … 3 screws damaged in the battle re-plugging power cable on VFE side solved the problem but … no obvious bad connection spotted … Further investigation : Access required !!! Is the problem really mechanical? Never LPC … So what’s about regulator boards? The box SM1 was checked fully functional after closure. And now?  1 RJ45 bad connection spotted on VFE side ( SM4 top ), previously left due to miss-interpretation : … expect others …

6 PS LEDs as Seen with PRS0 FEBs  PS/SPD> CROC / FEBs and LED TSB in PRS0 ( temporary ) steered locally ( CAT / PVSS )  Prototype CU + Final HV : nominal value of 550 V  Steering HV for PMTs, V LED via PVSS (final)  Acquisition with PS/SPD FEB FE-PGA spy-RAMs Test Sequence broadcasted on back-plane by PRS CROC / Triggers - LED TSB - FE-PGA RAM 30 cycles FE-PGA Read Start Signal max t channels Total charge LED TSB : external trigger out not seen (Jumper required?) V1V1 V2V2 V3V3 V4V4 V5V5 Tail

7 Measured Charge, Q, in SM1 NO HV (soft bug) Now Corrected VFE KO (no power?) BOTTOM TOP Max / Min is in Green Half Board Good Bad Evil Nominal HV 550 V Color Map: COLD MEDIUM HOT

8 The Good : SM1-B-VFE01 Stationary  2  G  Q rms on Q Q vs time Q stat. dist. Fluctuation dominated PMT Q 22 hottest coldest hottest coldest 500 evts / Ch. Non uniformity in charge ~5 results from: - Gain ( ~1.7 ) - Illumination Deconvoluate from source non uniformities - Assume cte light / Ch. - Q Density Time ( s ) Q

9 The Good : Timing, Shape & Gain Gain: Max / Min = in global agreement with LPC measurements But +/- 0.2 variations by Ch. Timing: Same t 0 for all Channels But …  varies … Corr = 0.8 with N  -e % Variable shape factors between Ch. rms on  ~10 % fluctuations within a Ch. N  -e  ) ( % )

10 The Bad: SM1-B-VFE03 G   2 / Q Additional noise ‘pollutes’ signal? From LEDs? Gain: 1.6 LPC Q stat. dist. OK coldest hottest  : % OK Pathologic Charge, Q Gain too high 2.1 vs 1.6 Timing & Shape OK Compatible with X-talk Q Density

11 The Evil: SM1-T-VFE02 Multiple peaks Multiple peaks Q: Saturation FE  2  G  Q Q stat. dist. rms on Q Q vs time hottest coldest strangest Fluctuations not dominated PM Q Time ( s ) Q Density Q 22

12 The Evil Continued: V LED Not possible to close the light !!! Strange behaviour of noise with V LED To be investigated further In good cases Signal saturation for SM1-TOP  V LED controlled via PVSS / calibrated with multimeter :  V LED tuned according to SM1-Bottom Nominal value No signal expected Q V LED ( V )  ( Q )

13 Tentative Tests With SPD VFE  DAQ Tests: Pattern injection from SPD VFE / PRS2 FEBs  Read SPD data with FEB : result = OK, but …  LED Tests: Flash SPD LEDs and read with PS/SPD FEBs  Half of the channels have SPD bit inverted ! ‘Mis-understanding between Barcelona & LPC’ Where to absorb it now? Not FEB level conclusion … a suivre … voir Rémi

14 Conclusion  PS/SPD FEB production on good way : C side should be equipped end of July Investigate VFE Powering issues / Dead contacts simultaneously  LED acquisition with FEBs performed in close to final state Further investigate noise / more statistics Investigate V LED behaviour  FE / VFE connection can tested from noise measurements solely but fragile … requires the crate to be sealed after … Fill in the Online Calo Logbook …