1. Torch electronics test environment MCP readout update

2. Torch MCP Readout Prototype. Mechanical packaging and PCB design. Three PCB flavours Stacked in a box type assembly. This is held together by two machined aluminium side plates (not currently shown in GA drawing) which contain slots for the readout cards to run in. MCP Motherboard provides Anode connectors and HV components Readout cards contain MCP anode/NINO amplifier circuits, HPTDC and FPGA devices and Ethernet transceiver hardware/connector. Clock/PSU board provides conditioned power plus synchronised global clock, and trigger signals to readout cards.

3. General assembly drawing

4. Packaging Issues Ethernet connecters are very bulky and snag vertically with adjacent readout cards in stack. This is because the anode connector pitch is set by the pitch between the MCP anode pins. One solution shown in general assembly drawing is to provide ‘either side mounting’ of Ethernet and anode connectors so all other components remain topside The second solution inverts the top and third card wholesale and handles the reverse order of the anode readout for the inverted cards in the FPGA by hardware selector link. The third solution is to take the Ethernet hardware off the readout cards and onto a daughterboard which plugs into the readout cards using compact high speed connectors.

5. MCP motherboard Requires some final positioning to HV ladder and connector Also requires an aperture for the MCP HV wires to exit through. Will finalise the above and have the PCB made when the actual MCP device arrives and we can check our design against the real thing.

6. Readout cards Under construction. Connector, NINO and HPTDC footprints made. NINO slow control/biasing circuits being designed and laid out (many thanks for guidance and assistance from ALICE group members and Ken Wylie). Rui Gao will discuss the digital area of the readout card separately.

8. Conclusions Have real progress on packaging and PCB design, but plenty more work to do. We have experienced some delays through selection and procurement of specialist components. Cannot start spending money on PCBs until designs are finalised. Production phase will be triggered when we can inspect our MCP and confirm the fit and function of the MCP motherboard. Packaging issues give an idea of the problems to be solved re. fitment of the 8*128 pixel MCPs and electronics to Torch prism faces in the real system.