[Halld-tagger] Fwd: Tagger microscope amplifier board files

Richard Jones richard.t.jones at uconn.edu
Mon Jun 20 18:19:43 EDT 2011


Fernando,

Agreed, we should do this.  Thank you for your work on this.  We will try to quickly turn this revision around and get a prototype populated within a few weeks.

-rtj


On 6/17/2011 10:23 PM, Fernando J. Barbosa wrote:
> Hi Alex,
>
> I forgot to mention this on my previous email. I suggest that you layout
> a prototype circuit to include 5 channels and a sum circuit to verify
> that it performs as intended before committing to a final complete PCB.
>
> Best regards,
> Fernando
>
>
>
> Fernando J. Barbosa wrote:
>> Hi Alex,
>>
>> I have attached a zip file containing an example layout for your
>> reference. I extracted the schematics from the files that Igor sent me
>> but is an exact functional replica. These include one amplifier
>> channel and the summing circuit of 5 channels.
>>
>> The layout is intended to minimize the signal path length which
>> improves signal integrity but at the expense of channel width. The
>> height is reduced, though.
>>
>> I have added layers with copper pours rather than using planes. This
>> is better for visualization purposes but you may choose to use planes,
>> instead. There are 6 layers in these sample layout with extensive
>> ground planes and one solid VCC plane. These facilitate direct
>> connections of GND or VCC pads.
>>
>> I used Mid-Layer 2 to route the input and output signals to and from
>> the sum circuitry. The other 4 inputs to the sum input should be
>> routed to the sum pad in a similar manner, a star configuration.
>>
>> I used Mid-Layer 4 to route the SiPM outputs which will connect to the
>> output connector. Other traces for gain setting, etc (basically DC)
>> may be routed on one of the poured GND layers but be sure to avoid
>> crossing, as much as possible and at 90 degrees, sensitive traces.
>> Also, make any of these DC bias, etc wide (25 or 50 mil).
>>
>> When you step-and-repeat the amplifier channels make sure that you
>> have enough GND between the channels to minimize cross-talk. It is
>> also possible to move components to the bottom layer if you need to
>> compact the layout a bit more but this will increase complexity during
>> assembly.
>>
>> I hope this helps. Thanks for your patience and best regards,
>> Fernando
>>
>> P.S. If you need me to check your design at a later date, please
>> create and include an integrated library file. This makes things a lot
>> easier for me.
>>
>>
>> Alex Barnes wrote:
>>> Hi Fernando,
>>>
>>> Thank you for your help.
>>>
>>> Sincerely,
>>> Alex Barnes
>>>
>>> On Mon, Jun 6, 2011 at 9:04 AM, Fernando J. Barbosa<barbosa at jlab.org
>>> <mailto:barbosa at jlab.org>>  wrote:
>>>
>>>      Hi Alex,
>>>
>>>      Sorry for the delay. I was off last week and I did not have access
>>>      to my PC. I will have a sample channel layout by the end of this
>>>      week which should allow you to proceed with the layout of the full
>>>      readout front end.
>>>
>>>      Best regards,
>>>      Fernando
>>>
>>>
>>>
>>>
>>>      Alex Barnes wrote:
>>>
>>>          Hi Fernando,
>>>
>>>          We haven't met but I'm Alex Barnes, a new graduate student
>>>          working in Dr. Jones' lab on the SiPM amplifier layout. This
>>>          summer I'll be analyzing the current amplifier board and
>>>          working in Altium on a new board. Would you happen to have
>>>          anything I could look at for the new board?
>>>
>>>          Thank you,
>>>          Alex Barnes
>>>
>>>          On Tue, May 3, 2011 at 4:34 PM, Igor Senderovich
>>>          <senderovich at phys.uconn.edu
>>>          <mailto:senderovich at phys.uconn.edu>
>>>          <mailto:senderovich at phys.uconn.edu
>>>          <mailto:senderovich at phys.uconn.edu>>>  wrote:
>>>
>>>             Hi Fernando,
>>>
>>>             I hope this finds you well.
>>>             Have you had a chance to play with the microscope SiPM
>>>          amplifier
>>>             layout? A student in our group, Alex Barnes, will begin
>>>          working on
>>>             the project in the next few weeks as the summer is
>>>          beginning and
>>>             we thought he can have some suggestions or base design from
>>>          you.
>>>
>>>             Please let us know.
>>>             All the best,
>>>             -Igor
>>>
>>>
>>>             On 3/29/2011 10:20 AM, Fernando J. Barbosa wrote:
>>>
>>>                 Hi Igor,
>>>
>>>                 Thanks for the update. I plan to start working on a
>>> sample,
>>>                 single channel layout later this week.
>>>
>>>                 Best regards,
>>>                 Fernando
>>>
>>>
>>>                 Igor Senderovich wrote:
>>>
>>>                     Hi Fernando,
>>>
>>>                     It just occurred to me regarding the Altium files I
>>>                  sent you
>>>                     with the tagger microscope amplifier design, that
>>>                  it may not
>>>                     have been updated since a fix done later on when
>>>                  testing a
>>>                     manufactured piece on the bench.
>>>                     Here is the most current circuit:
>>>
>>> http://zeus.phys.uconn.edu/wiki/images/AmpCircuit_v7_DC.png
>>>                     We reversed polarity to PNP of transistor 'm' (5th
>>>                  transistor
>>>                     from the left) I think the Alium files may not
>>>                  reflect this change.
>>>
>>>                     Please let me know if you find any other issues or
>>>                  discrepancies.
>>>                     Thank you,
>>>                     -Igor
>>>
>>>
>>>                     On 3/14/2011 10:26 AM, Igor Senderovich wrote:
>>>
>>>                         Hi Fernando,
>>>
>>>                         Did you get and were you able to open the files
>>>                      I sent you with
>>>                         the e-mail below?
>>>                         Let me know if you need any other material to
>>>                      work with our
>>>                         amplifier design.
>>>
>>>                         All the best and many thanks for your help,
>>>                         -Igor
>>>
>>>
>>>                         On 3/9/2011 10:54 AM, Igor Senderovich wrote:
>>>
>>>                             Hi Fernando,
>>>
>>>                             I am resending the tagger microscope
>>>                          amplifier package. It
>>>                             should have all the Altium stuff and files
>>>                          for procurement.
>>>
>>>                             Thank you for all your help with this,
>>>                             -Igor
>>>
>>>
>>>                             -------- Original Message --------
>>>                             Subject:     Tagger microscope amplifier
>>>                          board files
>>>                             Date:     Wed, 13 Oct 2010 15:38:46 -0400
>>>                             From:     Igor Senderovich
>>>                          <senderovich at phys.uconn.edu
>>>                          <mailto:senderovich at phys.uconn.edu>>
>>>                             <mailto:senderovich at phys.uconn.edu
>>>                          <mailto:senderovich at phys.uconn.edu>>
>>>                             <mailto:senderovich at phys.uconn.edu
>>>                          <mailto:senderovich at phys.uconn.edu>>
>>>                             Reply-To:     senderovich at phys.uconn.edu
>>>                          <mailto:senderovich at phys.uconn.edu>
>>>                             <mailto:senderovich at phys.uconn.edu
>>>                          <mailto:senderovich at phys.uconn.edu>>
>>>                             <mailto:senderovich at phys.uconn.edu
>>>                          <mailto:senderovich at phys.uconn.edu>>
>>>                             To:     Fernando J. Barbosa
>>>                          <barbosa at jlab.org<mailto:barbosa at jlab.org>>
>>>                             <mailto:barbosa at jlab.org
>>>                          <mailto:barbosa at jlab.org>>
>>>                          <mailto:barbosa at jlab.org
>>>                          <mailto:barbosa at jlab.org>>
>>>
>>>
>>>
>>>
>>>                             Dear Fernando,
>>>
>>>                             I am sending you the files associated with
>>>                          the SiPM amplifier
>>>                             board we discussed today.
>>>
>>>                                 * *AmpBoard.zip* contains the entire
>>>                          project that our
>>>                             student,
>>>                                   Mitchell "Woody" Underwood, compiled
>>>                          at the time of the
>>>                             board
>>>                                   layout. It should have the Altium
>>>                          files and all the
>>>                             materials
>>>                                   submitted during PCB manufacturing
>>>                          and population. Spec.
>>>                                   sheets on our SiPM and Transistors is
>>>                          included there as
>>>                             well.
>>>                                 * *SignalAnalysis.zip* has some traces
>>>                          and response
>>>                             function plots
>>>                                       o _Response functions_: there is
>>>                          a pdf with a plot
>>>                             of the
>>>                                         modeled response function and
>>>                          another with the
>>>                             measured
>>>                                         response (based on injected
>>>                          sine waves, not with SiPM
>>>                                         pulses) The measurements were
>>>                          done at the low gain
>>>                                         setting, which is the critical
>>>                          one for normal
>>>                             microscope
>>>                                         running.
>>>                                       o _Traces_: You will find some
>>>                          BMP files with
>>>                             oscilloscope
>>>                                         captures. Almost all of them
>>>                          (green trace) are of the
>>>                                         output from the summing circuit
>>>                          with only one channel
>>>                                         on. One plot has the output of
>>>                          the single channel
>>>                             (i.e.
>>>                                         signal extracted before summing
>>>                          circuit) in blue for
>>>                                         comparison. An accompanying
>>>                          README file explains the
>>>                                         file-naming notation to
>>>                          describe the conditions of
>>>                             the
>>>                                         measurement.
>>>
>>>                             One, sort of cross-talk-related issue I
>>>                          didn't mention is that
>>>                             there is a noticeable change in the summed
>>>                          pulse shape
>>>                             depending on whether the individual
>>>                          channels read. We have
>>>                             separate emitter followers for the outputs
>>>                          so we expected them
>>>                             to be well-buffered. The different trace
>>>                          captures compare the
>>>                             shapes based on what is plugged in.
>>>
>>>                             Thank you very much, Fernando, for you input.
>>>                             All the best,
>>>                             -Igor
>>>
>>>
>>>


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