Star-fst-l mailing list

[董家宁 <jndong AT sdu.edu.cn>]

Dear Gerard and All,
  Thanks for all the comments!

  1. Two biases for inner and outer hybrids:
  We'll add a jumper between the two biases, and use shared bias for 
inner/outer sensors as the default running scheme.
  P.s. We notice that there are jumpers used in hybrid for IST. Does anyone 
know the jumper type?
  
  2. Connector position & selection:
  1) We'll move the two connectors to the same side in T-Board. Right now we 
are working on it, and it seems like that keeping the current size is 
practicable.
  2) A survey about the connector selection will be carried out recently. We 
will try to find the best choice.
   (BTW the SAMTEC connector is reliable based on the previous experience, 
change to other connector may bring some unknown risk. Suggestions are 
welcome if one has better brand suggestion.)
   
  3. About the remote sense, do you mean the VSS_sense, VDD_sense and 
GND_sense? If yes, they are already connected. You can find them in pin 38, 
44, 50.
     So the minimum pin count for connector from T-Board is 22. But in this 
case, there are just 3 pins connected to VSS, VDD and GND. Usually, more pins 
will provide better power supply voltage if the size is acceptable. (In IST, 
7 pins are connected to VSS, 6 pins to VDD, 9 pins to GND ).

  Best,
  Jianing & Li


> -----原始邮件-----
> 发件人: "Gerard Visser" <gvisser AT indiana.edu>
> 发送时间: 2019-02-19 05:02:46 (星期二)
> 收件人: "LI YI" <li.yi AT sdu.edu.cn>
> 抄送: star-fst-l AT lists.bnl.gov
> 主题: Re: [Star-fst-l] Weekly FST meeting - 2/14/2019
> 
> hi Li,
>       Just a quick note to say I'll try to think about connector options 
> but at this 
> time, when my work for FST is still entirely without funding, it is 
> unlikely 
> that I can really attempt to search for an optimal connector. We hope the 
> funding contract will be in place sometime soon.
>       I do not believe that changing the connector incurs any real risk, 
> except 
> insofar as we don't really like the new type for some reason. Changing the 
> layout is not risky, and adding additional layers to the T-board should 
> that be 
> necessary is not risky.
>       I thought the connector used on IST should be ok; but if there is 
> report that 
> it broke (traces, presumably) under connect/disconnect we should think 
> strongly 
> about a better connector or layout. But I don't have info on such problems 
> in IST.
>       A smaller connector may exist, which could be helpful.
>       A connector which affixes to the boards and may be the means of 
> fastening the T 
> board to the detector assembly, as with the SSD "T-board" that I showed, 
> may 
> exist. And I think it could be very helpful, in the case of both connectors 
> on 
> one side for easy connection of the T-board+cable.
>       One which is both smaller and has mechanical features would be nice, 
> perhaps 
> there is something. That will be harder to find.
>       The minimum pin count for connector from T board to hybrid by my 
> reckoning is
> 
> 8 for APV signals out
> 4 for CLK & TRG to APV
> 1 for RST to APV
> 2 for SCLK, SDA to/from(SDA) APV
> 1 for bias "SUB"
> 3 (more better) for VSS, GND, VDD
> 
> that is 19 min, better something like 24 or 26 or so. Not 44 for sure. 
> There 
> isn't any harm in 44 pins if you've got room for it though.
>       (BTW I didn't remark on it before - sorry! - but looking at the 
> latest posted 
> schematic of the T board on 1/31, it seems the remote sense lines aren't 
> connected on the T board as we'd planned on doing? Do I misunderstand 
> there? Or 
> else this needs some small change.)
>       Sincerely,
> 
>               Gerard
> 
> 
> On 2/15/2019 9:22 AM, LI YI wrote:
> > Hi Gerard and All,
> > 
> > Thank you for the documents!
> > 
> > So the connector used in SSD is from
> > http://www.nicomatic.com/product-amm_micro_connectors-81-en.htm
> > Its pin size can go up to 50 pins. 44 pins are the minimum pins needed
> > for FST. SSD connector pin distance is 1mm, which is larger than the
> > previous one used in IST (which is 0.8mm). If SSD connector is more
> > reliable than IST one, we can switch to SSD (the space saved would be
> > small ~ 60/2*0.8mm-44/2*1mm = 2mm). Otherwise, we would prefer to use
> > the same IST one to reduce the risk of error in drawing.
> > 
> > Best,
> > Jianing & Li
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > On Thu, Feb 14, 2019 at 11:18 PM Gerard Visser <gvisser AT indiana.edu> 
> > wrote:
> >>
> >> hi Li,
> >>          Here for reference is info on the SSD "T-board" like thing, 
> >> that was mentioned
> >> in meeting discussion just now.
> >>
> >>          Gerard
> >>
> >>
> >> On 2/13/2019 6:02 PM, Ye, Zhenyu wrote:
> >>> Dear all,
> >>>
> >>> We will have a meeting to discuss Forward Silicon Tracker tomorrow at 
> >>> 9am BNL time. The meeting agenda and bluejeans info can be found at
> >>>
> >>> https://drupal.star.bnl.gov/STAR/blog/yezhenyu/forward-silicon-tracker-weekly-meeting
> >>>
> >>> Best,
> >>> Zhenyu
> _______________________________________________
> Star-fst-l mailing list
> Star-fst-l AT lists.bnl.gov
> https://lists.bnl.gov/mailman/listinfo/star-fst-l