E.Hazen Slides on faraday cage, PC boards, cabling Mezz Boards, - PDF document

Atlas Week October 2000 http://ohm.bu.edu/bmc/slides/atwoct00/ E.Hazen Slides on faraday cage, PC boards, cabling Mezz Boards, Cabling, Faraday Cage (general) mezz_evo.pdf Evolution of Mezzanine PCB Design ext_cables.pdf External Cable Proposal JO1.pdf Noise Coupling (J.Oliver) Module 0 JO2.pdf Shield Plane in F-Cage mezz_conn_mod0_ec.pdf Mod 0 Endcap Faraday Cage with Shield and connector endcap_mod0_exp.pdf Mod 0 Endcap Faraday Cage Exploded endcap_shield.pdf Mod 0 Endcap Faraday Cage Shield Plate Rev G (3x8) Mezzanine Lite Board HH_MEZZG.pdf Dimensions 1 of 3 9/29/00 3:38 PM

Atlas Week October 2000 http://ohm.bu.edu/bmc/slides/atwoct00/ Rev H (3x8) Mezzanine Lite Board HH_MEZZH.pdf Dimensions csm_adapter.pdf CSM Adapter Board mod0_cables.pdf 36-Pin Cables Production Proposals fig_cprime.pdf "2 Box" Shielding Concept new_fcage.pdf Endcap F-Cage for Production - Proposed new_fcage2.pdf Endcap F-Cage for Production - Proposed barrel_prod_1.pdf Barrel F-Cage for Production - Ideas mezz_conn_prod.pdf 36 Pin Connector Details 2 of 3 9/29/00 3:38 PM

Atlas Week October 2000 http://ohm.bu.edu/bmc/slides/atwoct00/ ship_box.pdf Hedgehog PCB Shipping Box 3 of 3 9/29/00 3:38 PM

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Mezzanine Lite Evolution Rev D - Oct 99 o RJ-45 connectors for JTAG and TDC o 10 produced o Worked pretty well but noise levels high Rev E - June 00 o 2mm header connectors o Board shrunk 8mm to fit inside patch panel o 10 produced in June 2000 Rev F - July 00 No Photo o Change from 4-6 layers, 2 ground planes o Noise now limited by clock pickup on hedgehog Rev G - Aug 00 o All external signals moved to 36-pin connector o 4 boards produced in Sept 2000 o 3 boards under test on chamber at Harvard- works well but AMT-0 locking is problematic Rev H - Sep 00 o Switch to AMT-1 TDC o Shorten board and move connector for compatibility with endcap chamber faraday cage o Now being tested!

ATLAS Week, August 2000 - E. Hazen MDT Electronics ATLAS External Cable Connections to MDT We propose to eliminate the patch panel and mount a single interface connector on each mezzanine board, with one cable per board to the CSM. We have prototyped and tested this scheme (report by J.Guimaraes/J.Oliver) Chamber Service Module DC Power Optical Fibres Latest mezzanine board layout Connector close-ups Current Status: Electrical concept proven. Halogen-free cables found Connectors found - some mechanical issues on chambers require further study

Noise coupling from TDC (digit al) t o analog input s • Dominant frequency range 5 MHz - 8 0 MHz (and beyond) • Magnet ic (induct ive) coupling : Current loops due t o common mode component of LVDS signals int o cable capacit ance Digit al power/ground current loop • Elect ric (capacit ive) coupling : Volt age noise on digit al power/gnd planes, common mode LVDS volt age. • Noise coupling is predominant ly down down t o MDTs and Hedgehogs TDC TDC ASDs ASDs

c) Aluminum shield plane at t ached t o faraday cage TDC TDC ASDs ASDs

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Module 0 Modifications (endcap) Hole in Cover Connector to CSM F-Cage Cover New Shield Mezz PCB Hedgehog PCB (Cover not shown)

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Module 0 Endcap Faraday Cage - Exploded View

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Endcap Faraday Cage (mod 0) Shield Plate

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS "CSM Adapter" for Testing Adapter box needed to test chambers before final CSMs installed - Convert 36-pin cables to RJ-45 for CSM-0 - Connect JTAG daisy-chain - Digital and Analog Power Distribution Prototype for 4 Mezzanine Boards built and tested Final version for 18 Mezzanine Boards - design underway JTAG in JTAG out DC Power TDC 1 TDC 2 TDC 3 TDC 4 Mezz 1 Mezz 2 Mezz 3 Mezz 4

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS 36-Conductor Cables/Connectors Lab Testing - use IEEE-1284 (parallel printer) type "CC" cables: Cheap, shielded twisted pair cable with reasonable performance. IEEE-1284 std cable construction http://www.connectpro.com/pccables.html For production, we need a flat, shielded, zero-halogen cable. Amphenol Spectra-Strip has quoted US$ 346.19/CFT 15/pair halogen-free, shielded and jacketed ($ 11.36/m) (quote was for 5000 ft; our total is about 30k ft) Connectors and labor add about $7 per cable. Estimated total is about $200k for 15k cables, total 10km length Original scheme with patch panel was about $180k (excluding design). So, up to the CSM the price is comparable.

c ‘) Faraday cage enclosing hedgehog - Mezz card in individual box (G.Hert en) TDC TDC ASDs ASDs

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Endcap Faraday Cage Proposal This is the "2 box" idea some of you may have heard about... One box covers the hedgehog PCB Second box covers the mezzanine PCB 36-pin connector Box 2 - shield over mezzanine PCB Box 1 - shield over hedgehog PCB

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Endcap Faraday Cage Proposal

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Barrel Chamber Faraday Cage What about Barrel Chambers? Propose to use same "2 box" scheme. Mezz board shield Hedgehog board shield Cable Exit Options: 1. End of Mezz shield 2. Over spacer (top view)

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Mezz-CSM Connector: Mezzanine End The IEEE-1284 std connector ("mini-centronics") is an attrative choice. The problem is that it isn’t infinitely small! Only 34mm is available for the "top exit" idea on the endcape chambers Worst case for endcap: 4x6 8.5 degree chamber Envelope Limit 10.0 mm Clearance 13.0 mm 34.0 mm Mezz Shield 11.0 mm PCB 10mm is left for cable exit. This is okay, but: No strain relief for cable is provided No latching mechanism for connector is provided (we can easily design a small sheet metal retainer) Barrel Chambers: Right-angle exit between mezzanine boards? Mezzanine PCB Shield

ATLAS Week, October 2000 - E. Hazen MDT Electronics ATLAS Hedgehog Board Shipping Boxes Each box holds two PCBs Connectors protected with cardboard tubes Folds up then slips inside sleeve Size: 6 x 24 x 36 cm Cost (100) US $4.37