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Re: Combined tracking meeting

Hi Gerard -

  thanks for your comments. Actually, the factor is 60, but if we are 
willing to compromise on the slow, forward going protons, we could
squeeze it. 

   I also talked to Fernando about the non-linear aspect, and he also 
mentioned that the ASIC will do that for us at some level. It would
be good to understand all of the effects involved.  Given the option of
stuffing the ~45 CDC modules with 14-bit chips might be a good
option to consider. 

  Cheers - Curtis
On Wed July 23 2008, Gerard Visser wrote:
> Hi Curtis,
> 	I read your doc, just wanted to mention that as far as the ADC125 is 
> concerned there would certainly be an option either to have it be 14 
> bits or to apply some nonlinear stage in the analog input signal 
> conditioning. Actually 14 bits has for a long time been planned as the 
> baseline pcb design so it can be stuffed either for 12 or 14 bits 
> operation, so that all is trivial (except for the higher price of the 14 
> bit chips). Nonlinear signal processing needs a lot of detailed 
> discussion, it is not going to get into this summer's pcb layout, but I 
> am pretty sure there will be enough room on the board to add something 
> if we need to in a future version. Of course if the ADC voltage scale is 
> made nonlinear the FPGA will also have to transform it back (with more 
> bits) to linear form before integrating the charge, etc. But this should 
> be feasible.
> 	Asking for only a factor of 20 in dynamic range sounds low, but I'll 
> wait to hear details at the meeting...
> 
> 	Gerard
> 
> Curtis A. Meyer wrote:
> > Hi Everyone -
> > 
> >   there will be a combined tracking meeting on Monday July 28 at
> > 1:30pm. I have created the Wiki page and put a couple of items
> > on the agenda. Please add appropriate items as people see
> > fit.
> > 
> >    - Curtis
> 



-- 
Professor Curtis A. Meyer        Department of Physics
Phone:  (412) 268-2745          Carnegie Mellon University
Fax:    (412) 681-0648            Pittsburgh PA 15213-3890
cmeyer@ernest.phys.cmu.edu  http://www.curtismeyer.com/