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HV plateau
Hi All,
I made a HV curve by counting the tracked cosmics i obtain in a certain
time window (40'). The results are in top of the usual CDC ASIC tests
page:
http://www.jlab.org/Hall-D/software/wiki/index.php/ASIC_design_optimizations
One can see a plateau starting at 1750 V.
Cheers,
Yves
/--------------------------------
/ Yves Van Haarlem
_--~~--_ /
/~/_| |_\~\ / Carnegie Mellon University
|____________| / Department of Physics
|[][][][][][]|:= / Wean Hall room 8404
__| __ |__ \ Pittsburgh, PA 15213
| ||. | == | | \ USA
(| ||__| == | |) \
| |[] [] == | | \ Tel.: +1 412 268-6949
| |____________| | \ +1 412 641-9252
/__\ /__\ \ Fax.: +1 412 681-0648
~~ ~~ \-----------------------------------
On Wed, 9 Apr 2008, Fernando J. Barbosa wrote:
> Hi Yves,
>
> I could not find anything physically wrong or bad with channel 16 that could
> have caused this failure. It may have been due to assembly as this package is
> not sealed.
>
> Regards,
> Fernando
>
> Yves Van Haarlem wrote:
>> Hi Fernando,
>>
>> Very nice that you found the problems. I guess the bad solder joints were
>> good when I got the interposer and became bad after a while - I am not so
>> worried about that. But channel 16 on the preAmplifier died at some point -
>> you can see it dying (on March 6, 2008) in the data. As far as I remember
>> we did not do anyting to the pre-Amplifier on that day but it is already a
>> month ago. Maybe you have an idea what could have damaged the pre-amplifier
>> because it should be avoided in the future.
>>
>> Cheers,
>> Yves
>>
>>
>> /--------------------------------
>> / Yves Van Haarlem
>> _--~~--_ /
>> /~/_| |_\~\ / Carnegie Mellon University
>> |____________| / Department of Physics
>> |[][][][][][]|:= / Wean Hall room 8404
>> __| __ |__ \ Pittsburgh, PA 15213
>> | ||. | == | | \ USA
>> (| ||__| == | |) \
>> | |[] [] == | | \ Tel.: +1 412 268-6949
>> | |____________| | \ +1 412 641-9252
>> /__\ /__\ \ Fax.: +1 412 681-0648
>> ~~ ~~ \-----------------------------------
>>
>> On Wed, 9 Apr 2008, Fernando J. Barbosa wrote:
>>
>>> Hi Yves,
>>>
>>> I verified that the interposer had some bad solder joints and these have
>>> been fixed. The one you have should be good.
>>>
>>> I checked the amplifier and indeed channel 16 was not working. Further
>>> tests revealed that the ASIC A input (for negative going signals or
>>> anodes) has been damaged. The B input (for positive going signals or
>>> cathodes) works fine.
>>>
>>> Because I don't have additional preamp cards, I suggest that Gerard send
>>> you his preamp and I will send him yours, which he can use for his tests.
>>> I will ask Elke for additional funds to produce a few more preamp cards
>>> (we have a few ASICs left).
>>>
>>> Gerard, let us know if if this works for you.
>>>
>>> Regards,
>>> Fernando
>>>
>