Feb 10, 2011 SiPM Electrical and Cooling
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Contents
Background information
- Files for discussion
- Hall D BCAL Readout Mechanical Concept (Jim Fochtman)
Action Items from previous meetings
- Run his cooling model simulation for the situation when the electronics was turned off (Jim)
- Update Npe numbers on dynamic range table to include effect of attenuation length (Elton)
Tentative Agenda
- Announcements
- Schedule, reporting, and manpower (Elton)
- First article testing (Carl and Yi)
- Mechanical cooling (Jim)
- Temperature compensation (Jack)
- Preamp-summing (Fernando)
- Discussion
Minutes
Attendees:
- Announcements
- Schedule, reporting, and manpower (Elton)
- First article testing (Carl and Yi)
- Mechanical cooling (Jim)
- Temperature compensation (Jack) Jack is in Baltimore, but sent the following updates
- I have a solution for 3 - 7 C that will keep divider errors within 6% with nominal 1% (EIA-96) resistor values. The error can stay within about 4% if the trim resistors are selected from the 0.5% values (EIA-192).
- This solution appears to be also very close for operation at 18 - 22 C but has an offset. This could be compensated for by modifying the Vsupply when operating at the 20 C range.
- This approach works for any arbitrary Vbr for a SiPM but imposes a requirement that we group the SiPMs so that the values of the Vbr are within 0.2 V or better. Error drops within 5% if the binning is by 0.1V Vbr steps. I think that may be difficult. Grouping the SiPM devices that share similar Vbr *may* not allow this simpler solution given the number of devices and the number of bias supplies.
- I'm now looking more closely at a slightly more complex passive solution that would still require binning the devices by Vbr but could widen the range to perhaps 0.25V or 0.4V. This solution uses a pre-trim divider network to widen the allowable Vsupply. It adds two more resistors to each passive divider (all EIA-96).
- The total power consumption would again rise - but only slightly. The trade-off there is power consumption for immunity to count rate gain shifts.
- Preamp-summing (Fernando)
- Discussion