Minutes of the FE Electronics Meeting

 
       Date:      25/05/98    9:30 - 10:30 
       Present:   J.J.Wang, H.Kolanoski, Z.Zhu, M.Pohl, U.uwer

       Agenda:    1.  ASD8 Status
                  2.  Power Distribution Boards
                  3.  HV Boards
                  4.  Test Pulse distribution
                  5.  Analog Readout
                  6.  AOB
        

        

  1. ASD8 Status:
  ---------------

  1.1  Bidding of ASD8 order for 7800 boards out:
       expect decision by begining of June. First
       boards in around 6 weeks.

  1.2  Status of 850 high pt boards: 
       Assembly has started. 850 Boards ready by end of June.


  1.3  ASD8 Note:   
       It was proposed to collect the different information on the 
       ASD8 boards in form of small internal notes on well defined
       topics (e.g.: operation point of ASD8, crosstalk, noise
       behaviour). This information should then serve as a basis
       for a paper on the amplifier board (beginning of autumn).
       U.Uwer should prepare a list of necessary items. 

  1.4  Longterm failures:
       A test of the 1996/1997 amplifier boards was proposed to
       get information on the failure rates of the boards.  
    
        
  2. Power Distribution boards:
  -----------------------------
 
  2.1 Triggered by changes in the power distribution 
      the ASD8 ditribution boards will include in future 
      fuses (10A) and LEDs for power indication.

      The size of the boards will not change.
    
  2.2 Five boards are assembled and are undergoing tests right now.
      The Software was updated to account for the 2 different threshold
      values of the board. 
      It was decided that a system test is necessary to check the 
      longterm stability of threshold and test-pulse. The cosmic
      setup and the Zeuthen TDC system can be used together with 
      a CAN-Controller.

 
  2.3 Answer to E.Michel's question:: The voltage drop of 0.5~V is 
      independent of the number of ASD8 connected to a board. It is 
      determined by the RC filter.

 
  3. HV boards:
  -------------

  3.1 The amount and the type of HV boards which have to be produced
      must be defined by Hamburg / Mike. Boards will be produced
      according a specific order. Every board will have a unique 
      label.

  3.2 Tests:
      J.J.Wang is preparing a test-setup which allows on one side
      for a burn-in of the boards and on the other side a test of the
      HV board. The tests includes HV stability and signal decoupling
      to test the soldering. The test should be done at 2.5 kV.

      The test-setup should forsee a flushing with nitrogen although
      we should try first to test in air.
 
      An open question is still the burn-in time: J.J.Wang will try 
      to get information on the required time and how to speed up
      aging.
          
       
  3.3 Cleaning of the boards and effect of colophonio was not 
      discussed.     



  4. Test pulse distribution boards:
  ----------------------------------   
     not discussed.



  5. Anaolg readout board:
  ------------------------

  JJ.Wang mentioned the problem to have several trigger modes. 
  The need of the self-trigger was underlined. 

  The discussion was shifted to a dedicated meeting. 



  6. AOB 
  ------

  6.1 Radiation tests:
      U.Uwer is in contact with Mr. Boden from HMI. Gas-boxes for the 
      HV board-test are in construction.


  6.2 Next Meeting:
      As date for the next meeting Tuesday, 2nd of June was proposed.