Aug 23, 2011 SiPM Electrical and Cooling
From GlueXWiki
Action Items from previous meetings
- Decide on cable connections for monitoring cable from Bcal wedge to patch panel. Consider electronics needed for pulsing system (Elton and Fernando)
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Clarify option of purchase of additional SiPMs (Elton) -
Send optional values for 86KOHm resistor to Chris to investigate delivery times (Jack and Chris) -
Order micro Dsub connectors to make connections to the monitoring control board (Chris)Options in progress: a) purchase crimp tool for local assembly of cables, b) order specialized cables c) purchase premade cables with limited lengths.
Tentative Agenda
- Announcements
- Action Items
- Schedule, reporting, and manpower (Elton)
- mini-Bcal
- SiPM production testing (Yi)
- Mechanical assembly (Jim)
- Temperature compensation (Jack)
- Electronic boards (Fernando and Chris)
- Light guide gluing setup
Minutes
Attending: Elton, Jack, Fernando, Nick, Jim, Yi, Ivan
- Announcements
- Action Items
- Schedule, reporting, and manpower (Elton)
- mini-Bcal
- See Log Entry for LED and cosmic pulses
- Pulses seem to have an extended tail out to 180 ns. This may be due to after pulsing with the shaping due to the quenching resistor.
- SiPM production testing (Yi)
- Ivan s starting to work on fitting data taken to study cross talk and after pulsing. Presently investigating the fitting function
- Elton: Have we gotten the data on the radiation badges placed on the mini-Bcal during the beam test? No. Yi will follow up on this.
- Elton: Would it be useful to have a high school student from the Governor's school work on cross-checking the USM sensors at JLab? Yes.
- Mechanical assembly (Jim)
- Gluing fixture improvements completed. Will try to order if accounts are opened.
- Drawings for mechanical readout parts were completed by James (now back from medical leave). Chuck was checking them. Subassembly drawings are next.
- Temperature compensation (Jack)
- Checked errors introduced on the slope for current resistor sets. Maximum deviations are on the order of +/- 1%, which is fine.
- Optimization on resistor values for the board continues. However, Jack will check if the resistor sets on the pre-production boards is within specs and freeze them.
- Jack is working with resistor values for 383 sets (groups of 10), but we should have 400 sets. Note that 8 sets are on the mini-Bcal and 8 sets are on the pre-production units. That leaves 1 set (10 units) unaccounted. Needs to double check with Yi and his data base to sort this out.
- Electronic boards (Fernando and Nick)
- Resistors of 90.0k 0.1% for the preproduction boards have been ordered.
- Boards have been populated and bias tested for downstream. Voltages are off but calculations uses resistor values need to be updated.
- Voltage tests are consistent between boards at the 4 mV level.
- Still need to place the order for the UFL cables for the preproduction boards. Will do this Friday so that the readout packages can be completed.
- Light guide gluing setup