1. FE electronic box Construction of end piece OT module Electronic components Mechanics Cooling

2. End-piece Feed trough boards at dummy

3. End piece The OT module exists out of two identical panels holding 64 straws. 2 Feed trough boards connecting HV and gnd over full width to outside world

4. End-piece construction

5. Feed-trough boards

6. Electronic components Overview of boards Full or half module Stacking of boards HV and connector section

7. Electronic components Feed-trough board 2x HV-board 4x ASD-board 8x OTIS-board 4x GOL-board 1x

8. Full or half module GOL/OTIS board design is made in such a manner that it can switch from left to right

9. Stacking of boards 2 planes of 64 channels 32 channel HV-boards Each HV-board connects 2 ASD-boards 2 ASD-boards connect L or R OTIS OTIS-board L and R version GOL-board connects 4 OTIS-boards front and back plane

10. HV connector-section 4 HV-boards make an enclosure so HV is completely shielded from other electronic parts HV space contains 4 boards carrying 32 cap each that are integrated in the board HV-distribution inside One side HV is coming in other side is low voltage and couples to ASD board trough frame plate.

11. Disconnected FE-box Fast replacement FE-box is fully decoupled from chamber

12. Connected FE-box full HV-enclosure Forces from gnd- spring are not on chamber Gnd spring over full width 128 gnd contacts on each side

13. Spaces for gas-pipes Gas-pipes OT-module has a free space on each side of 5 mm for gas pipes FE-box can easily be removed

14. FE box overview

15. FE-box exploded view

16. Frame 3D

17. main mechanic parts One plate supports gol/aux boards 2 equal support plates on both sides, supporting HV-boards, ASD boards and Otis board. 2 extraction/insertion tools are implemented Guiding tip guarantees proper mating with chamber connector A C B D

18. Box-enclosure

19. Cooling Location of dissipating areas Heat transport trough the frame Heat transport from chips to frame measurements

20. Dissipating areas

21. Frame sideview

22. ASDBLR COOLING CONSTRUCTION

23. ASDBLR AS TEMPERATURE SENSOR ~750mV ~1.8mV/C We use a dummy input diode as temperature sensor (Not callibrated yet)

24. NTC 5K on Copper Surface Close to ASDBLR Each board has a sensor Connection point

25. OTIS NTC NTC UNDER OTIS ON OPOSITE SIDE

26. PACKAGED FRONT END COOLING TEST The Front Ends of the Outer Tracker are closely packed, heat must be extracted with cooling water along the Aluminium cooling extension plate. For the test we use a cooling block with forced air Several sensors monitor heatup of components.

27. Proto Outer Tracker Front-End Tests 27 EFNI H K 35 C Otis 52 C ASDBLR NTC on copper 42C ASDBLR Input Diode 43C RESULTS AFTER SETTLING

28. NTC GRAPH K ohm temp

29. 25 50 30 35 40 45 12 Hours COOLING BASE 6321 RED ASDBLR NTC ON Copper Board SURFACE 42C BASEPLATE THERMOMETER 35C t=0 >power on REMARKS: 1.forced air cooling base with regulators, shifts 10C 2.ASDBLR steps up 5C in 2 minutes, then settles to 7C above plate 3. OTIS settles 17C above cooling flap part of baseplate OTIS Copper NTC 52C BLUE ASDBLR DIODE ~43C ASDBLR 17C 8C FIRST IMPRESSION FROM PAPER RECORDERS AFTER POWER SWITCH ON

30. FIRST CONCLUSIONS The ASDBLR has low temperature rise thanks to strong thermal coupling trough PCB Delta T=7 degrees C The maximum delta T is 17 degrees C for the Otis chip The regulators are mounted directly on the cooling plate, no internal sensor available, but adequate cooling is ok.