D0 Calorimeter Electronics Upgrade Meeting Minutes

August 27, 1999

Meeting time is 10:30 am, Fridays in DAB1. Video connection available.
Contact Leslie Groer groer@fnal.gov.

= ACTION ITEM

Solenoid Tests

DH - Solenoid data is available at 10 second intervals.  Not in format to be put in Excel spreadsheet unfortunately, as it is on a separate system.  DH will get data over a 10 hour period - resolution of about 1000 points should suffice. Will have to time synch with the Excel data.  Toroid data is being logged already.
Fan speed is being logged - both the old & new fans' r.p.m. changes by about 100 out of 3000 with solenoid on.  DH needs to check the correlation with the toroid as well but suspects it has minimal effect.
Field measurements in the BLS crates on the platform were about 100 gauss on top and 10-20 below, very dependent on how close you are to parts of the steel in the crate.  This is from the toroid, nothing seen from the solenoid.
They are running the toroid at about 1500 amps which is below saturation of the muon iron.

The ICD has not measured the field for their boxes as far as we know.

DH has a new preamp PS going - wants to check the shunts for the current measurements, they might get hot.  A copper heat sink to the water manifold might be needed.
PL reported that 5 monitor boards were stuffed by Bob Jones group (3 done).  They can do more - just need to get in their queue.  We can test one of these in the French pulser PS as it is not being used at the moment.

6" wafers should be here soon.  They have produced 2 lots x 24 wafers and all are good.  We will get the 32 we ordered.
ASAT have stalled on packaging the 4" wafers - they want to know what the process was that made the pads, in particular the material + thickness.  DH has asked people he had contact with at Orbit/Supatech but doubtful will get a lot of information.  We believe they used a standard 2-micron process.
PL has been testing SCAs in the burn-in stand.  One died out of 49 (4", die-up).  Had problem running teststand as the soldering iron nearby crowbars the power rail.  This led to a discussion on workspace.  We will need to find benchspace eventually for PS testing (especially for reworking BLS PSs) and SCA testing.  MT will talk to Rick Hance when it becomes appropriate.
PL checked on the price for probing SCA on wafers before packaging.  Cost is about $28/wafer and packaging is about $0.70 each.  We lost about 15% of wafers before in the 6" line, most near the edge.  It seems cost effective to probe. PL will check on the PO for the probing and packaging - was cut before.  We might get the wafers shipped directly.

DS reported we have lost a lot of the space above the BLS racks in the CC due to the muon chambers.  The muon fibers need to run above the top of one of the racks.  Ed Podschweit has recabled one of the BLS CC crates as a test - he did a good job getting stuff into a much smaller space (2/3 the width and 1/4 the height). This took him a couple of days.  The power cables got buried however and we might want them accessable.  The covers will need a few "bumps" to accomodate the cables.  Three more CC racks need to be recabled.  This is waiting on what we decide we need to do with the power cable harness which will need to wait until we know what we are doing with the BLS transformers.  Will take about a week to do and will need to be put in Ed's queue.
The voltages and currents will be different for the BLS and the power harnesses need replacing - this will be quite a bit of work.  They go to different places and are of a different gauge.  DS would like at least 1/2 a crates worth of BLS's before finalizing the design (he projects this will be after November).
MT commented that there is contract help available from the lab - all we need do is ask!  This needs to be done as plans firm up.

Lee Sawyer and JDH been fixing their motherboard design with the help of DS.  Fixed the filtering.  The signal decay time is very long and still not understood.  They have type A preamps from LB to check against the type I prototypes to get a comparison.  The PMT voltages looked OK.  LB suggested the ICD group (JDH) send status reports to her before the Calorimeter upgrade meeting.

French 4th (and final!?!) preamp pulser fanout board is being sent to FNAL.  Should be here next week.  We should check the layout so they can go into production.

Labels are ordered (ed note: most of the labels were picked up on Friday afternoon) - we are getting 70k 1.5" and 100k white + 20k yellow 0.8" labels.  Shaoa Fu has the layout for the barcodes and will work with Ed Podschweit to produce labels for the parts we have.

The four preamp motherboards v3.2b need to be assembled.  A couple of new vendors have been contacted and Chipco in Indiana will be tried for these 4 boards.  They have very good pricing.  CH and MG will work on getting parts and diagrams together for the assembly.  MT suggested we might want to visit the vendor and we could discuss them doing other jobs for us as well.

Metrocircuits is quoting 6 weeks delivery of the remainder of the motherboards and will keep the specs within 0.072".

LB has been in contact with UTY but no purchase order yet.  She will set up a telephone conference for Tuesday with UTY and KTY.  (ed. note: PO arrived Tuesday but KTY did not join conference call).  LB also asked for KTY to send us a report before the Friday meeting but did not receive anything this week.

LB has all the parts for the H test-jig, apart from a couple of mix-ups that are being fixed.  She will get these assembled soon.

LB has quotes from 3 companies and expects 2 more for production of the H species preamps.  One vendor asked about using SMT resistors instead of silk-screened. LB will check into this and get requotes as this might be a cheaper option.  Quotes received so far are in the range of $30-$50 per preamp.  There is a concern that the small SMT resistors needed (0402 or 0805?) have enough power disappation and that values in the correct range can be found.

LG needs to produce a list of all the tasks needed for preamp motherboard stuffing to get a quote.

LG  will check whether putting some baffles in the preamp box to affect the air flow makes any difference.  We probably should move the temperature probes so that they are not in contact with the side of the box and will give a more reliable measurement of the air temperature.

LG showed some plots of coherent noise measurements with pulser cables connected and disconnected and also with a modified preamp motherboard where the pulser input resistances have been increased by a factor of 10.  There is a clear difference between the coherent noise with and without pulser cables connected (either the black cables from fanout to backplane or the yellow cables from pulser to fanout).  The correlations on boards with pulser cables disconnected are fairly consistent with a zero correlation.  This needs to be investigated further.

LG spoke to some of the Level 3 people about readout of the DAQ in November.  There is a chain that will read out one crate in the MCH that has been tested but DS mentioned that the T&C and clock signals will need to be modified to get anything besided pedestal values.  Further investigation and work needs to be done on this before we can test the full system. Gennady Briskin will be at FNAL September 13-17 and LG will get together with him.

DE and DS are checking the design changes to the Timing and Control.  DE will start simulating this next week.  Once the bugs are out, this section needs to be integrated with the rest of the board.  These changes might exceed the current FPGA so they may have to go to the spare.