sPHENIX discussion of electronics

["Boose, Stephen" <boose AT bnl.gov>]

Martin,

I'm waiting for a license so I can look at the Gerber file of the panel. This 
will tell us the exact offsets of all SiPMs. Then after establishing the 
fiducial position, software looping with those offsets should get us to each 
location. I'm sorry that I found it necessary to upgrade from GRBL 0.9 to 1.1 
during the process of getting a utility to work but the good news is that the 
upgrade to 1.1 is supposed to provide smoother movement and added commands 
for jogging. The UGS utility shows you what GRBL commands it uses when you 
ask it to move, which I think is very useful.
- I had noticed that the X and Z axes were backwards, I was wondering how 
that happened. That would just be a polarity change in the commands though.
- Mike cut a length of scintillator which I crookedly plugged into the light 
plug just to test light levels. Sal then added a sleeve to keep light from 
splashing on the other SiPMs and he made another plug which we'll be able to 
test soon.
- In my quick test the four SiPMs in a group showed currents that agreed 
within about 2%. The problem is that I noticed a large residual leakage 
current which I traced to a ground loop in the Kiethley system. If you unplug 
one of the connectors (sense?) in the back of the Kiethley it goes away. I'd 
like to test it with another Kiethley as a check.
- Right now the LED is being powered by a precision current source, this is 
"Continuous" mode. Next is to test "Pulsed" mode in which the signal 
generator provides the pulse length but the Controller sets the pulse 
amplitude. It's entirely possible that for acceptance testing of these panels 
Pulsed mode will be overkill, but it seems that we haven't had that complete 
discussion yet.

Cheers,

Steve Boose
sPHENIX Experiment
Brookhaven National Laboratory
BLDG 510C
Upton, NY 11973
Phone: 631 344-2897

   


 

-----Original Message-----
From: sPHENIX-electronics-l <sphenix-electronics-l-bounces AT lists.bnl.gov> On 
Behalf Of Martin Purschke
Sent: Wednesday, March 18, 2020 3:55 PM
To: sphenix-electronics-l AT lists.bnl.gov
Subject: Re: [Sphenix-electronics-l] No Calorimter Elecronics meeting today, 
18-March-2020

Eric, all,

let me add a bit of info about the "new" SiPM tester that Tom, Sean and I had 
spent a lot of time with.

After the 3x3 board that allows us to mount a complete 3x3 panel became 
available, we re-arranged the setup and, most importantly, the scan head. The 
head is now able to reach every SiPM on the larger panel.

I wanted to use the time we have now to adapt the scanning procedure that Tom 
and I had endlessly tuned and perfected to the new head and board assembly. 
Sean and I looked at the new setup today. We had to re-route a few cables as 
they would have gotten in the way of the moving "carriage". Sean and I were 
able to do that, and the head can now go anywhere it needs to.

I uploaded a few pics so everyone is on the same page at 
http://www.phenix.bnl.gov/~purschke/boardtesting_updateMarch18.pdf

Unfortunately, I found that none of the automation scripts we developed works 
any longer. The reason is that the firmware of the CNC controller has been 
upgraded, and this has broken every low-level utility Tom and I had made. So 
right now I'm unable to move the head in an automated fashion, and, more 
ominously, I cannot read back the positions the way we did before. I was able 
to connect to the terminal and trick the system into moving, but the position 
report that we used is just gone.
Presumably there is an alternative somehow, but this will take some doing. Oh 
well.

Also, Tom and I had at some point re-wired the motors so we had a 
right-handed coordinate system the way you look at a normal x-y plot on 
paper, with z going "up". x and z have now reversed their sense of direction 
- good that we caught the latter as we might have driven the head into the 
SiPMs.

We will have to re-do the lower-level stuff to drive the head.

Best,
        Martin



On 3/18/20 11:28, eric mannel wrote:
> I hope everyone is in good health and not stressed out about the 
> current situation around the world.
> 
> In place of the regular meeting, I just want to send around some 
> updates as I understand them.  If anything is incorrect, please send 
> me the correct information.
> 
>  1. As many of you know, Universities are starting to close up to
>     different degrees.  I encourage everyone to follow the rules even if
>     it means we start to fall behind schedule.  BNL is still open for
>     employees (although we are encouraged to stay home) and mission
>     essential visitors but that might change.  Bottom line, stay home  
> 2. SiPM delivery and testing is complete and operations at UofM are
>     essentially ended.  It would be nice to get some kind of technical
>     note on the process written up. It should include a summary of the
>     results and what we learned.  Nathan, can you take the lead on that
>     with input from the Debrecen and UofM groups?
>  3. HCal pre-production electronics have been delivered to the HCal
>     group, with the exception of a few final signal cables that Al is
>     working on.
>  4. HCal production electronics orders are being prepared.  We are
>     waiting on quotes for a few boards.  The SiPM board assembly order
>     has gone out. PCBs should arrive late April.  The SiPMs still need
>     to be kitted for delivery to CEM. The pigtails are due to arrive
>     mid-April. The Meritec cable order for the internal HCal cables has
>     been placed. I need to discuss with Frank and Danny if we have
>     sufficient BNL resources to do thte final termination or if we need
>     to outsource that part. Power cables have been ordered and may
>     actually be delivered.
>  5. EMCal pre-production Electronics: I delivered a significant portion
>     of the SiPMs to CEM today for the next round of assembly.  The PCB
>     order is still on schedule for a April delivery based on information
>     from Monday.  Assembly will start mid-April.  Internal signal cables
>     continue to come in, with another batch arriving Friday. QA testing
>     identified only one bad cable. Steve and I are going to start
>     working on getting RFQs out for the production electronics.
>  6. Digitizers: Columbia is "work from home" only.  The XMIT PCB order
>     is in transit and the digitizer PCB order is slated for a mid-April
>     delivery. Assembly will not start until Columbia resumes operation.
>  7. Bias Supplies: The Bias supply order is working it's way though the
>     BNL procurement process.
>  8. Racks: Steve and I are working on getting rack layout drawings to
>     the Infrastructure and Integration team for discussion and
>     approval.  We have tentative estimates on the power cable lengths,
>     but need a final consensus on lengths to request quotes.
> 
> Eric
> 
> --
> Eric Mannel, Ph.D.
> PHENIX Group
> Dept of Physics
> Brookhaven National Lab.
> 631/344-7626 (Office)
> 914/659-3235 (Mobile)
> 
> 
> _______________________________________________
> sPHENIX-electronics-l mailing list
> sPHENIX-electronics-l AT lists.bnl.gov
> https://lists.bnl.gov/mailman/listinfo/sphenix-electronics-l
> 


-- 
Martin L. Purschke, Ph.D.        ;   purschke AT bnl.gov
                                 ;   http://www.phenix.bnl.gov/~purschke
                                 ;
Brookhaven National Laboratory   ;   phone: +1-631-344-5244
Physics Department Bldg 510 C    ;   fax:   +1-631-344-3253
Upton, NY 11973-5000             ;   skype: mpurschke
-----------------------------------------------------------------------
_______________________________________________
sPHENIX-electronics-l mailing list
sPHENIX-electronics-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/sphenix-electronics-l

Attachment: scint2.jpg
Description: scint2.jpg