31.7.
Matej tested 4 HDIs (8030-8033 and 8010). 8010 had a faulty TBM which was replaced, however, during subsequent tests, other TBM (the one which was working fine!) started sparking during HV test. Burn marks visible under the microscope in the top-right corner of the right TBM, between wire-bond pads. Other HDIs were fine and were glued to 2 v4 modules (1523 and 1529) and 1 v3 module (1526).
1.8.
Prepared the software and hardware for the full-qualification of multiple modules in parallel. Ran reception test on M1520 and M1522.
2.8.
Ran full qualification on M1520 and M1522. It consisted of qualification at -20, IV@-20, 5 cycles between -20 and +10, qualification at -20, IV@-20, qualification at +10 and IV@+10. This set of tests will from now on simply be called "full qualification". For some reason, second qualification at -20 failed. M1522 shows significantly high leakage current compared to previous tests
5.8.
Boxes 2 and 9 have been filled with L1 module trays. Each tray can hold 4 modules and each box contains 13 trays. Box 9 filled with humidity collecting balls. M1520 and M1522 placed in the box 9 which is the box that should be filled first. Reception test was run on M1523 and M1526. There were a lot of issues with M1523 in the address decoding test affecting other tests as well. What was found out is that the third dac, Vsh, was set to the wrong value by default if one was making module configuration folder using mkConfig script. It was 30 and should be 8. This should be propagated in pXar later on.
6.8.
Started running reception tests with 3 modules (1523,1526,1529) in parallel, but with the corrected value of Vsh (8). Several issues were observed.
First, one of the DTBs had a connection timeout which appeared every time we tried the reception test. Changing the DTB didn't work. This was solved by plugging the USB cable on the PC side to a different USB slot
Second, pretest in the reception test did timing test which we deemed unnecessary so it was removed.
Third, results for 1523 and 1529 didn't look correct. It was as if there was a problem with either timing or dac values. Comparing the logfiles of the test and the pxar files, it was found out that the timing settings were correct. The issue was in the dac settings taken by elComandante. What we forgot was that elComandante does NOT take dac settings frmo the module folder, but rather from generic tbm folders like tbm10d. This is set in the elComandante.config. The issue was that tbm10d folder had wrong values for Vsh (30, instead of 8) and ctrlreg (0 instead of 17). After this correction reception tests ran fine.
PixPhOptimization.cc was edited to correct the starting values of the parameters for the PhOptimization test. The old values were sometimes causing the tests to algorithm to fail even though the chip was fine.
Started full qualifications of all 3 modules, but there were some issues with the coldbox. It was noticed when it was not cooling at the start of full characterization. The warning on the coldbox interface read "Geber-stillstand". Danek managed to make it go away by stopping the program, even though no program was being run.
Finally, full qualification started around 15:00, finished at 22:40.
M1523 failed first qualification at -20, but finished other two qualifications. IV curves for that module were taken while M1529 was stuck and connected to HV as well meaning that the readings are actually sum of IVs from these two modules.
M1529 failed first qualification at -20, few seconds apart from M1523 failure. One of them failed during the Gain Pedestal, other one on PhOptimization. It also failed other two qualifications (PhOptimization and GainPedestal)
M1526 had no issues in qualification, however, it was graded C. One chip was problematic in most of the tests, while 4 others had issues with TrimBits. This is a bit suspicious so we'll investigate it further.
7.8.
Investigating problems with qualifications on testboards 0 and 1. We noticed that it happens during PhOptimization or GainPedestal. Also investigating why M1526 failed trimbits test on several ROCs. The cause was identified as a memory leak (several Gbs!) during a PhOptimization scan. Separate log made for this.
8.8.
Started full qualification WITHOUT PhOptimization at 9:15 on modules 1523, 1526, 1529. Finished after 8 hours. 1529 had a reception test error during fulltest@+10, other tests ran fine. Glued protection caps on 4 modules - 1504,1505,1509,1520 using 2 component epoxy adhesive.
9.8.
Running fulltest@-20 and +10 for modules 1504, 1505, 1520. The plan is to irradiate them in Zagreb and evaluate the changes induced by radiation. |