Proposal for NSW chamber PCB layout and alignment

Proposal for NSW chamber PCB layout and alignment (updates) Givi Sekhniaidze CERN, 14 -15 April 2014 1

Some remarks about mechanical layout After the discussions with G. Spigo and M. Ciapetti and checking the sector layout and overlap regions the angles for the MM modules defined: • LM 1 – 33° • LM 2 – 8° • SM 1 & SM 2– 21° Small and large sectors will have the different pitches for the strips (450 μm for LM and 425 μm for SM) The PCBs will NOT have the equal height: • For intermediate PCBs (PCB 2, 3, 4 for LM/SM 1 and PCB 7 for LM/SM 2) it will be calculated as 1024 x Pitch (460. 8 mm for LM and 435. 2 mm for SM) • The rest of the module height will be equally distributed between external PCBs • The height of the external PCBs will be slightly larger then intermediate (example: 474. 4 mm vs. 460. 8 mm for LM 2), but due to the spacer/mesh frame (25 mm minimum) the active area will be less. Givi Sekhniaidze CERN, 14 -15 April 2014 2

Givi Sekhniaidze CERN, 14 -15 April 2014 3

Givi Sekhniaidze CERN, 14 -15 April 2014 4

Overlap Givi Sekhniaidze CERN, 14 -15 April 2014 5

Proposal for PCB alignment (MSW version) • We propose to have one pair of the precise hole and slot in the central part of the PCB • Precise hole will be used ONLY once during positioning on the gluing table • In the frame of the panel could be glued precise insert (Inox, PEEK, etc. ) for alignment with other panels Assembling holes Precise slot Precise hole D Assembling holes Givi Sekhniaidze CERN, 14 -15 April 2014 6

Proposal for multi-PCB alignment 3 board version Precise holes in the table Panel assembling table Givi Sekhniaidze CERN, 14 -15 April 2014 7

PCB in-plane alignment Additional Targets/images Precise hole Read-out strips MSW version MMFE-8 Strip 513 Strip 512 Givi Sekhniaidze CERN, 14 -15 April 2014 8

Alignment check of PCBs on readout panels Measurements taken with a laser machine from NA 62 lab (CERN-PH -DT)

� Readout Eta Scan direction Srrips roted to the PCB edge Alignmen t pin Scan performed on both sides of the readout eta panel with the precise pin inserted in the same hole on the two sides

� Pins alignment (x-axis of 1 side re-scaled)

� Strips far from the pin δ < 20 μm • Strips close to the pin δ ≈ 35 μm

Assembling holes for LM 2 chamber • As an example, part of the PCB 6 from LM 2 chamber • The assembling holes are equally distributed in the frame area • Only one hole in the center of the connector area Givi Sekhniaidze CERN, 14 -15 April 2014 13

MMFE board and spacer/mesh frame • The dimensions of the MMFE board will be 50 mm x 215 mm • The space between spacer/mesh frame and edge of the R/O board – 55 mm (50 mm MMFE width + 5 mm clearance) MSW NSW MMFE Givi Sekhniaidze CERN, 14 -15 April 2014 14

Assembling holes in connector area • Preferable position for assembling holes w. r. t. connector would be in the center of the connector (free space between two Zebra connectors) Assembling holes R/O strips Zebra connectors Givi Sekhniaidze CERN, 14 -15 April 2014 15

Summary • The draft version for the PCB layouts are ready – Missing the routing for the Zebra connectors – need position of the holes – Number and positions of the interconnection holes to be decided a. s. a. p. – Final decision about dimensions and the shape of the spacer/mesh frame (combined or separate) is needed to finalize the PCB design (resistive strips, HV distribution, pillars, etc. ) • Alignment method for the PCB positioning – MSW version + Saclay + other ideas? • Other targets/images for in-plane alignment to be implemented in PCB design? • Other wishes, ideas, suggestions? Givi Sekhniaidze CERN, 14 -15 April 2014 16