Stave 4028 Thermal tests Electrical tests

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Stave 4028Thermal testsElectrical tests
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4028 THERMAL TESTS

• We have studied the effect of the liquid speed on
  the modules heating.
• Test 1 all 13 modules are powered and configured
  (SURF and ROD) about 50 W
• Test 2 measure of (DT/power) for each module
  powered one at a time (only half stave - SURF).
  Is it possible to set a threshold for the
  variable DT/power as we have done until now
  indipendently of the cooling variables?

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General conditions

• We are using 2 indendent circuits to cool down
  the stave and the box
• T_CoolingStave -20C
• T_CoolingBox -6C
• T_InsideBox 3C
• Speed of the cooling inside the Al pipe set to 1
  (slow), 4, 8 (fast).

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Example of monitoring on 4 modules

• Test 1 all modules powered

Test 2 modules powered one at at time
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Example of temperature monitoring on 4 central
modules
Speed 1
Speed 4
Speed 8
Speed 4
Speed 1
Speed 8
Test 1 all modules powered
Test 2 modules powered one at at time
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Results of Test 1 (all modules on)
Cooling direction
When speed is low 1 -4, there is a significant
increase of temperature along the stave (Tmax
Tmin 10C!) A better uniformity is achieved
incresing the cooling speed (Tmax Tmin 4C)
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How cooling speed change the DT/power?
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4028 Electrical tests

• LOAD/STAVE tests are performed using 2 SURF
  boards.
• Comments
• In the STAVE macro with respect to the list, it
  is not included DVDD scan as DVDD is not
  controlled by TDAQ anymore but by ambush. The
  scan can be done modyfing the ambush script but
  
• Threshold scan with HV off with SURF is sometimes
  very different from scan HV off with MAC (due to
  my SURF or my script??).see slides 10-11

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Example of T monitoringduring STAVE
testMODULES 7-13 TEMPERATURE7 hours for half
stave (source excluded)
Test 510237
Test 510803
Test 510864
510893
510844
510405
510396
510803
510237
510864
Cooling flow
Module Test direction
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HV off with SURF or with MAC
Noise 400e!
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Then the analysis finds Unconnected bad
pixels with this low rows peculiar pattern!
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Electrical tests analysis

• STAVE\FLEX Comparison done using the official
  STAVE cuts without cut on HVoff data (as there is
  the source scan).
• LOAD\BURN comparison done with the official LOAD
  cuts (but some fake problems as HVoff is
  unusually good)
• The two modules with pre-existing large defects
  increase the number of bad pixels during loading
  and cycles.
• In 2 modules new small defects (about 20 pixels)
  are visible between chip 4 and 5 after loading.

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Bad pixels
Increasing in pre-existing defects
New Defect between 4 and 5
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M2a and M4a
There after loading is there anything that can
damage that point?
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M5a
225
81
159
Increasing both in loading and cycling
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M6A
135
299
320
Increasing mainly in loading