Re: Frontend & Thermal Management HallD

[John Schaapman <jsch@phys.ualberta.ca>]

Hi Fernando,
  I have just a few comments on your excellent report.

section:

2. The ASIC preamp.
   Has Mitch Newcomer indicated that the previously mentioned submission 
date to MOSIS of Feb 12 will be missed and why?

3. The Preamp Card
   a) I'd just like to clarify that two versions of the 24 channel card 
will still be required due to the fact that the input signal polarities 
of the anodes and cathodes are opposite. A third version may be needed for 
the CDC if it is in the chamber gas and requires low outgassing material.
   b) The input connector could be a source of problems since there are 
not enough signal grounds. Adjacent signal pins could create unacceptable 
crosstalk and too few grounds could lead to signal reflections and more 
crosstalk. I realise that there is very little space but this arrangement 
should make us nervous.

4. Thermal Management.

   You have specified a power supply input of 3 volts minimum for operation and
your thermal calculations so far. It would be nice to know at some point what
the maximum supply voltage would be due to thermal limitations. This would help
set the tolerances required for the power supplies and distribution system.

John

  

-- 
John Schaapman                   Ph: 780-492-3043
Centre for Particle Physics     Fax: 780-492-3408
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University of Alberta            
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