Readout for the minical and Tile-HCAL prototype, 15’

1. Readout for the minical and Tile-HCAL prototype, 15’ • The VFE RO: • The light signals • Photo-detectors • 1) APD’s (Hamamatsu, ) • 2) Si-PM’s (MEPhI) • 3) MA-PMs(Hamamatsu) • 4) MRS-APD’s(Obninsk) • Preamplifiers, shaper • charge sensitive (ECAL-LAL, Minsk) • voltage sensitive (Prague) • the electrical signals • 0-3Volt range, • dyn. range 1-75 (100) MIPs/cell • 20-40 ns rise • 150 ns (95%) • buffering and multiplexing • digitising • calibration and monitoring • The different photodetectors • front end electronics (VFE) • time schedule, needs • event format and DAQ (P.Daucey) 1. 2003 minical 2. 2004-2005: pre-prototype Tile-HCAL ECFA-DESY Workshop, NIKHEF

2. The light signals • produced number of photons by MIP: • ~ 150 ph/MIP/tile, loss in fibre-RO: ~20%, • tile; • = 1/3 cell 1 (absorber plate+tile) deposes ~24 MeV • >> in a cell ~ 72 MeV • maximal energy deposit/cell ~ 4.5 GeV (in rare tails) • ratio maximum/MIP = 65 ECFA-DESY Workshop, NIKHEF

3. The photodetectors The photodetectors receive the light from the scintillator tiles of the sampling calorimeter. options studied are: -Si-APD's, with 3x3 to 4x4 mm2 photo-cathodes, in arrays of individuals or matrix assembly, as in study at Hamamatsu, Japan and -Si-PM's, with 1x1 to 2x2 mm2 photo-cathode, from MEPhI/PULSAR(Moscow), 576 >>> 1000 pix/mm2 All systems are in still in development, no dedicated choice can be made at present. ECFA-DESY Workshop, NIKHEF

4. Required gain for pre-amps, 2 options • A) for APD’s: • 150 photons/tile = 450 photons/cell, ~80% transmission, • 80% photo-conversion efficiency: • possible intrinsic gain ~200-400 (to be verified) • >>> 15 000 - 30 000e-/ MIP= 7.2-14.4 fC/cell • conventional stable intrinsic gain ~50-100 • >>> 4 000 - 8 000e-/ MIP= 1.8-3.6 fC/cell • slope/width of photodetector signal: • ~ 2-5ns/20-30 ns width • required dynamic range: 65! • If MIP in cell channel 16 • >>> 4.5 GeV: channel 3000, • 12 bit ADC, ch 4096 = 3 V and • >>>> ch 16 =12 mV • preamp gain required:12 mV/7.2 fC = 1.7 mV/fC • 12 mV/1.8 fC = 6.8 mV/fC Resolution: 10 bit ADC: -4.5 MeV/bin 12 bit ADC, -optimal in range: ~ 1 MeV/bin ECFA-DESY Workshop, NIKHEF

5. Required gain for preamps, 2 options • B) For the Si-PM's: • much less preamp gain is needed • SiPM intrinsic gain is ~106 • a VFE RO-board development is under way • at MEPhI and PULSAR (both Moscow), • based on the H1-PM preamps. • They also look in an alternative pre-amp/shaper concept. • more on the photodetectors and pre-amps can be found in: • http://www.desy.de/~korbel/see/HCAL_Main_60902.ppt and • ....../DESY-Zeuthen_4.12.02.pdf. ECFA-DESY Workshop, NIKHEF

6. more on preamplifiers for APD’s • CALICE-ECAL: • prototype: ~10 mm2 preamp chip, modified OPERA type for APD • modifications specified and simulated in chip, design ready • next week submission of modified design for prototypes 25 x18 ch. • delivery in June 2003. Use in minical Summer 2003 • Minsk/Protvino: • 2 types tested with APD and MIP’s • 10 preamps available • 100 preamps in February 2003, • design of 16 channel MPC prototype: • (~ 8000 Euro needed??) • Prague (I.Polak): • voltage amplifier, (probably not optimal for APD’s??), • signals seen in DESY test, signal/noise??? • agreed to produce 16 channels PT end Febr. 2003 • development financed by Prague • DESY • trans-impedance type, tested with APD’s, • mod. CMS-type, cheap !, P. Smirnov • Test of all oreamps from above in minical tests when available in time. • Decision on what to use in preprototype: October 2003 ECFA-DESY Workshop, NIKHEF

7. Electrical signals from the minical CAMAC Read-Out, LC-2249A MA-PM as photodetector now up to 144 channels needed in summer 81 Si-PMs 27 APDs 3 MA-PMs (up to 48 channels) • Noise, randoms • cosmics • LED-pulses ECFA-DESY Workshop, NIKHEF

8. More on photodetectors Detailed investigation of available photodetectors with 55 cm2 scintillator tiles in test beams MIP peaks clearly separated from pedestals. • satisfactory performance • none yet tested in high field • all will be used in minical to establish performance and get operation experience • than decision which to use!! PM pre-amp, DESY-H1 pre-amp from MEPhI Hamamatsu,multianode PM,44mm2pixel MEPHI, Si-PM, 11 mm2 pixel Q sensitive pre-amp, Minsk V sensitive pre-amp, Prague Hamamatsu,APD, 55 mm2 Hamamatsu,APD-array,11 mm2 pixel ECFA-DESY Workshop, NIKHEF

9. The VFE-ROB-scheme Online Gain/HV monitoring? PIN diode for LED monitoring LED signals beam cosmic HV for Photo detectors Trigger/ RO clock pedestals Array of Photo detectors sensitive preamps pulse shapers Sample & hold Multi plexer (analog) ECFA-DESY Workshop, NIKHEF

10. The Read-Out Boards (VFE-ROB’s) for prototype It is foreseen to place the photodetectors on the surface of a ROB (read-out board), as tight together as possible, on special sockets to be developed, about 108 (6 x 18) pieces on one board. For the Si-PMs probably 3-4 times more have to be placed on a ROB. About 10-12 ROB's are needed for the Tile_HCAL prototype end 2003. (1000-5000??? channels) The signals from the pre-amps, which have to deliver signals of 8mV/fC input charge, have to be shaped (shaping time ~ 80-100 ns) and stored in sample and hold (S&H) pipelines for a time period of about 1-2 msec. Than a multiplexed read-out, clocked by the DAQ, will empty the pipelines. ECFA-DESY Workshop, NIKHEF

11. Calibration on VFE-ROB’s • Cosmic muon calibration: • the FE boards should be permanently operational to allow, • between test-beam pulses, • continuos collection of the low rate cosmic muons • penetrating the calorimeter, • which are used for real time on-line calibration. • They generate their own calibration triggers. • Low rate process, for precise calibration of whole chain • Preamp calibration: • by charge injection, >> • dynamic range • linearity, • high rate process, tests electronic chain only ECFA-DESY Workshop, NIKHEF

12. Studies with CALICE-ECAL chip Cinjection Chip VFE Diode Icalib R L Electronic calibration Polarisation (-200V) Le premier PCB du prototype physique 6 circuits de calibrage opérant sur 18 diodes chacun Déclenchement Calibrage ECFA-DESY Workshop, NIKHEF

13. Photodetector monitoring on VFE-ROB’s • LED monitoring: • The ROB should also integrate • a few light emitting diodes (LED's) • with LED-light distribution by clear optical fibres. • to all individual photodetectors • for stability monitoring, • and also to a few stable Si-photodiodes • (stable against temperature and bias voltage fluctuations) • to monitor the LED light output. • The analogue signals of the LED monitoring photodiodes • and the Si-PD’s (some?) • have also to be amplified, shaped • and stored in the same S&H pipeline. • LED monitoring has to be triggered in the gaps • between the test-beam pulses and during the read-out! ECFA-DESY Workshop, NIKHEF

14. More on VFE-ROB duties • The ROB has to integrate • the active elements (chips, to be developed) and in tight package • all the signal lines up to the S&H and multiplexer, • the power lines for the • individual photodetectors • (~400V for the APD's, or ~30V for the Si-PM's), • where each photodetectors operation voltage • will be adjusted individually • for equal gain on the level of ~0.1V. • It is hoped, that we can profit considerably from • the design of the ROB prototypes of the • CALICE-ECAL at LAL/Orsay. Group strongly interested in taking over VFE and DAQ duties: DUBNA: (I. Golutvin, I. Tyapkin) ECFA-DESY Workshop, NIKHEF

15. channel architecture, chip ECAL >> HCAL Detector Amp DC block On chip Charge preamp shaper Track & hold Vdc = -200V OPA LAL-Oray, F. Richard,dela Taille, offered to us to modify the ECAL-preamp/shaper chip for the requirements of the Tile-HCAL APD’s >>>>> ECFA-DESY Workshop, NIKHEF

16. pre-amp layout FLC_HCAL chip Rst_R Vbiaso_pa Vbiasm_pa Vbiasi_pa Vb_casc Vbiaso_sh Vbias_cell V_rf In 0 Vdda Vbiasi_sh Ck_R R Vss Vf H 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 1 In 1 48 Out 0 In 2 2 Out 1 47 FLC_HCAL CQFP 64 package In 3 Out 2 3 46 Out 3 4 45 In 4 Out 4 5 44 In 5 43 Out 5 In 6 6 7 42 Out 6 In 7 Out 7 8 41 In 8 9 Out 8 40 Vss Out 9 10 39 In 9 11 Out 10 In 10 38 Out 11 In 11 12 37 Out 12 13 36 In 12 Out 13 35 14 In 13 Out 14 34 In 14 15 Out 15 33 In 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 In 16 Vss Vdd In 17 SW1 Vdd Out17 Out 16 SW2 Out Out_pa Bias_out Vss Vdd Q_R Bias_buf FLC_HCAL pinout 25/03/03, LAL Package : CQFP64 2,5mm 1,7mm 64 pins Charge inputs Voltage outputs MUX output ECFA-DESY Workshop, NIKHEF

17. LAL/Orsay studies for Tile-HCAL pre-ampssimulation studies for linearity Linearity shaper/buffer Linearity preamp ECFA-DESY Workshop, NIKHEF

18. LAL/Orsay studies for Tile-HCAL pre-ampsoutput signal shapes Output signal preamp Output signal shaper ECFA-DESY Workshop, NIKHEF

19. FLC_HCAL characteristics, next steps 25/03/03, LAL 18 charge inputs/18 voltage outputs/1 MUX output Gain= 6.7mV/fc  450 fC max input charge (70 MIP) 2.8V dynamic range below 1% non-linearity • DESY will order 25 of such prototype chips • at the 7.April 2003 • >>> 25 x 18 =450 preamp channels delivered in mid June 2003 • DESY gets test-board from LAL • line driver prepared to run 30 channels for APD-minical studies • (July-September 2003) • If prototype chips are ok, we have enough channels to equip the • APD-cells (100-300, to be decided in May) of the prototype • calorimeter! ECFA-DESY Workshop, NIKHEF

20. Draft of conclusions from the DUBNA meeting • We need: • ~ 1000 RO-channels at beginning of 2004 for the 1m3 prototype test • --APD’s (Hamamatsu) and Si-PM’s (MEPhI) will be used • --photodetectors and preamps have to be optimised soon! • --The size of APD’s will be ~3x3 mm2 • the gain required was specified, • the combined gain of APD and preamp should result in 2-8 fC/MIP, • the electronic noise should be below 4-5 sigma of MIP, • the capacity of the APD’s will be ~ 25 pF, • the stability of the MIP signal should be in the range of 1%, • shaping time has to fit to the minimum bunch distance (180 ns), • dynamic range required between MIP(4 bit) and max. signal is >/~65 ECFA-DESY Workshop, NIKHEF

21. Draft of conclusions from the DUBNA meeting • Due to the short time available • we probably have to proceed in 2 stages: • 1. Use CALICE-ECAL VFE board with minimal modifications • keep 108 channels/board • keep ECAL preamps, noise,shaping,... • modify implementation/arrangement of photodetectors on board • modify photodetector power supply • add LED monitoring for all channels • ..... • 2. Design a versatile VFE concept allowing use of different competing • elements (preamps, HV distribution, monitoring..) • 3. When useful VFE boards available for first 1000 channel tests: • and more experience gained, (probably 0.5-1 year later) • implement optimal preamps (capacity, noise, gain), shaping • optimise power supply and individual adjustment • optimise online LED stabilisation ECFA-DESY Workshop, NIKHEF

22. The VFE-ROB-scheme, APDs Online/Offline Gain/HV monitoring? PIN diode for LED monitoring LED signals beam cosmic HV, 380-420V dV/V~10-4 DAC Trigger/ RO clock Charge injection pedestals Array of single APDs or matrices charge sensitive preamps pulse shapers Sample & hold Multi plexer (analog) ECFA-DESY Workshop, NIKHEF