1. LED Board for the Tile Calorimeter of the ATLAS Detector at the LHC
Titus Masike
Reto Suter

2. Brief Outline Large Hadron Collider ATLAS Detector TileCal
MobiDICK4 System
LED Driver
Tasks at Hand
Review of old Schematics
New Schematics
Design of the Board
OrCAD Capture
PCB Editor
SAIP Conference
Second Phase of Project
Re-redesign of Schematics
Production of First LED Board
Production of Second LED Board
Adjustments for Next Model
Conclusion
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

3. Large Hadron Collider
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

4. ATLAS Detector
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

5. TileCal
Stands for Tile Calorimeter. Used to measure the energy and trajectory of the particles produced in the proton-proton collisions in the inner detector. The TileCal measures by means of light pulses which are boosted into signals in photo multiplier tubes.
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

6. Photo Multiplier Tube Depends on two physical discoveries:
Photo Electric Effect
Secondary Emission
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

7. MobiDick4 System
During the shut down there will be a consolidation integrity check on the electronics which will be carried out by the MobiDick4 system
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

8. MobiDick4 System
MobiDick stands for Mobile Drawer Integrity Checking system. The initial MobiDICK system was used to check whether the integrity of the super-drawers of the TileCal hasn’t been compromised. The new and improved MobiDick4 system shall include several state of the art boards which will each provide a different function to the motherboard. Wits HEP group were given the chance to work on two of the daughter boards, namely being the LED Driver and the High Voltage board
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

9. MobiDick4 System
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

10. LED Driver- Old Board
The purpose of the board is to produce a -20V 20ns width almost square pulses out of a control signal that is 3.3V.
The board uses a component called a monostable, which is powered by about 5V, to generate a signal that will be split into two signals to feed to different branches of the shaping circuit.
Each one of these branches uses the 24V to produce the required pulse and width. The control signal comes from the MobiDICK base motherboard.
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

11. Tasks at Hand Review of Schematics Proposal of new Schematics
Convert Schematics from PDF to Electronic Format using OrCad Capture
Do a physical layout of the board using PCB Editor
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

12. Review of Old Schematics
The current board was made 10 years ago. So as you can imagine a lot of the parts on the board have currently been discontinued and are very hard to find. For this reason a new board is needed is currently being designed
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

13. New Schematics
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

14. New Schematics
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

15. Design of the Board
In order to design a board on computer you some sort of electronic CAD program. In this case the Cadence package was used, which is basically an assembly of about 13 programs but only two of the thirteen were used:
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

16. OrCad Capture
The original layout of the board was only available in PDF format so one of the tasks I was dealt with was to convert the LED Driver schematics from PDF format to Electronic format. The program used to do this is called OrCAD Capture from the Cadence design package. What this program does is that it makes the schematics for your board which basically are just the logical connections between each of the components on the board
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

17. OrCad Capture
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

18. PCB Editor
The PCB Editor program is dedicated to the design of all the physical components of the board ranging from a single component or part to the physical layout of the board itself.
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

19. SAIP Conference
Presented the projected at the SAIP 2013 Conference in Richards Bay
Poster Presentation
Was the only third year student at the conference
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

20. Second Phase of Project
Done by Reto Suter
Focuses more on the building of the design and testing
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

21. The Re-redesign of the Schematics
A lot of the parts I had used in my design could only be found in CERN
We wanted the board to be produced in South Africa
Hence why a re-redesign of the board was necessary.
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

22. Production of First Prototype
Very first LED board produced by wits
Had a few heating problems
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

23. Production of Second Prototype
Much wider than previous prototype
Converters put in so it can be powered by either 12V or 24V
Rather large resistors put in to dissipate heat
Four indication LEDs can be attached
A remote signal can be put in at J8
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

24. Adjustments for next Model
J7 component should be moved a millimetre to the right
Relay should be closer to the control pin of the converters
LED board for the Tile Calorimeter on the ATLAS detector at the LHC

25. Conclusion Very special thanks to Prof Bruce Mellado Robert Reed
Carlos Solans
Alberto Valero
Reto Suter
LED board for the Tile Calorimeter on the ATLAS detector at the LHC