Notes from Teledyne meeting

November 4, 2002


  1. The latest MCM PWBs still did not get countersinks in the backside for the nano connectors.
  2. For the flight production we need to decide on just one set of holes for the nano connectors.
  3. The thermal boards do not need all SMT parts mounted.  Only mount those shown on the drawings for the thermal boards.  About 13 boards have already been loaded with all parts, which is okay.
  4. The thermal boards do not all need to be wire bonded or even have ICs mounted.  Teledyne only needs to mount and wire bond enough ICs on the thermal boards, or other dummy boards, in order to be adequately prepared for production of the functional MCMs.
  5. Brian will verify that enough parts remain for the 13 functional boards.
  6. Both thermal MCM drawings were modified to include the polyswitches instead of zero ohm resistors.   Teledyne needs DXF files for these new drawings.
  7. Brian needs to know the specifications on the gold body of the functional MCM PWBs.
  8. Brian will formally notify SLAC of Teledyne’s intention to change the encapsulation material.  The new material is Hysol FP4450 for fill and FP4451 for dam.  Tom will update the materials list.
  9. Brian observed some cracking of the green solder mask on the Young Electronics boards in the region right around the mounting holes.  The cracking only was evident after SMT mounting.  He will investigate this problem.  Possibly it can be avoided by using the plastic cups on the mounting screws at this stage, to act as washers.
  10. Teledyne needs more black MCM shipping and handling boxes.  Tom will ship at least 30 from SLAC immediately.
  11. The PWB for the functional MCMs has an error causing inversion of two differential signals from the controller chips.  Teledyne agreed that they can correct this by crossing the wire bonds.  SLAC needs to correct this on the boards to be made for the flight production.
  12. SLAC needs to make wire bonding diagrams for both chips and send them to Teledyne.  The GTRC wire bonding diagram needs to show the crossed wire bonds.
  13. Teledyne needs a layout picture of each of the 3 ASICs (GTRC3, GTFE-F2, and GTFE-G) to use for orienting the chips during die attach.
  14. SLAC will Fed-Ex 4 of the new PWBs (without radius) on Tuesday, so that Teledyne will receive them on Wednesday.  They will be used for programming the pick-and-place and solder dispensing machines.
  15. Teledyne also needs a few more PWBs with radius, in case that the yield is not 100% for the flex attach.
  16. Robert measured the resistance from power to ground on one of the MCMs assembled at Teledyne.  The results are
    1. AVDDA to GND = 48 ohms.
    2. DVDD to GND = 131 ohms.
    3. AVDDB to GND = no connection
    4. Bias to GND = no connection
  17. Teledyne will build half of the functional boards with the G-version GTFE and the other half with the F-version GTFE.