1. HF ROBOX PRR3 Apr 2003E. Hazen HF Front-End Electronics ● System Description – Overview – PMT Board, ROBOX, Patch Panel – Signal Cable, Front-end boards and Crates ● System Performance – Noise Levels, 1pe signal, crosstalk – Tests remaining – Grounding optimization – EMC ● Current Status, Production Plans

2. HF ROBOX PRR3 Apr 2003E. Hazen HF Electronics Overview HF Readout Boxes 24 PMTs each Cable Route ~5m through shielding Electronics Housed in standard racks (3U card cages)

3. HF ROBOX PRR3 Apr 2003E. Hazen PMT to QIE connection PMT Anode 50Ω coax Coax shield ground at each PMT base Overall shield connected to QIE ground Separate Ground for each PMT QIE Signal Input QIE Reference Input PMT Box Two pairs per PMT channel Multi-pin shielded (MDR-36) connectors Skew-Clear ~50  single-ended to ground Patch Panel

4. HF ROBOX PRR3 Apr 2003E. Hazen PMT Base PCB Base Supports 8 PMTs with HV distribution Rear detail showing dual coax (signal plus reference) for each PMT

5. HF ROBOX PRR3 Apr 2003E. Hazen ROBOX Patch Panel MDR-36 Signal Connectors HV Connector Calibration Fiber Connector N2 Gas Connector Rear view (area to be potted)

6. HF ROBOX PRR3 Apr 2003E. Hazen MDR Connector SignalRef Signal ReturnRef Return Shield 12-pair Skew-Clear cable handles 6 QIE channels Each channel has: Pair 1: Signal, Signal Return, Shield Pair 2: Reference, Reference Return, Shield Overall Shield connected to metal connector backshell

7. HF ROBOX PRR3 Apr 2003E. Hazen HF PMT Signal Path Octal PMT Boards 16 (short) coax 12-pair Skew-Clear Readout Crate Patch Panel ROBOX (24 PMTs) 6-Channel QIE Boards Fiber to Readout

8. HF ROBOX PRR3 Apr 2003E. Hazen PMT Base PCB K Dy1 Dy2 Dy7 Dy8 V1 V2 GND V3 Filter/Divider for 8 PMTs K Dy1 Dy2 Dy7 Dy8 Last 2 dynodes individually powered R/C Filter per PMT Main GNDPMT GND (Individual)

9. HF ROBOX PRR3 Apr 2003E. Hazen Amphenol Skew-Clear TM Cable ● High-performance, compact ● Available in zero-halogen version (ATLAS, CMS) ● Terminates to convenient Mini-D connectors with overall metal shell

10. HF ROBOX PRR3 Apr 2003E. Hazen Skew-Clear Cable Drawing Will supply zero-halogen version on request

11. HF ROBOX PRR3 Apr 2003E. Hazen Front-End Board Input from 6 PMTs Honeywell VCSELs QIE DigitizersChannel Control ASICs CERN GOL (Gigabit Optical Link) Transmitters

12. HF ROBOX PRR3 Apr 2003E. Hazen HF QIE Crate Layout QIE Board 6 Channels 4 Boards= 1 ROBOX Clock and Control Module (3 boards; 4 slots) Standard 3U subrack (custom backplane) Calibration Module (5 slots) Total Power ~85W per crate

13. HF ROBOX PRR3 Apr 2003E. Hazen Grounding – Overview HV PS Safety GND Detector Frame Safety GND FE Electronics Diff Amp PMT Ground must float (but is cap-coupled to detector) HV Ground must float (Series R at ROBOX) QIE ground = local PMT ground QIE differential input (reference) returned to PMT to cancel CM signal

14. HF ROBOX PRR3 Apr 2003E. Hazen Grounding... some details How to interconnect PMT grounds, ROBOX case, and PMT shields for minimum noise? Under study...

15. HF ROBOX PRR3 Apr 2003E. Hazen Some Test Results ● Test setup: – Robox with prototype patch panel – Skew-clear cable with MDR-36 connectors – “Production prototype” QIE boards ● Results Presented – Scope trace of pulses showing speed – Noise measurement (pedestal) – 1pe peak (LED pulser attenuated to << 1pe level)

16. HF ROBOX PRR3 Apr 2003E. Hazen Average, Typical LED Pulses

17. HF ROBOX PRR3 Apr 2003E. Hazen PMT Gain vs HV 3 planned voltages corresponding to different eta regions 1700V: 5E5 (81 fC) 1400V: 2E5 (32 fC) 1100V: 5E4 (8.1 fC)

18. HF ROBOX PRR3 Apr 2003E. Hazen System Noise Performance (1pe Levels 1100V: 8.1 fC 1300V: 32 fC 1500V: 81 fC) Rms= 2.3 fC 2.1 fC 2.2 fC2.7 fC2.1 fC

19. HF ROBOX PRR3 Apr 2003E. Hazen 1500 V 1pe measurement

20. HF ROBOX PRR3 Apr 2003E. Hazen 1pe peak vs HV 1100 V1200 V1100 V 1500 V1600 V 1700 V 1300 V1400 V

21. HF ROBOX PRR3 Apr 2003E. Hazen Status and Plans ● All components have been prototyped ● Lab testing of full system underway ● ROBOX performance meets requirements but beam test is required to confirm total system performance. ● Production of electronics chain outside ROBOX will begin after testbeam experience.