Stave 4028 Thermal tests Electrical tests 4028 THERMAL

Stave 4028 Thermal tests Electrical tests

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?

General conditions We are using 2 indendent circuits to cool down the stave and the box • T_Cooling. Stave= -20 C • T_Cooling. Box = -6 C • T_Inside. Box = 3 C • Speed of the cooling inside the Al pipe set to 1 (slow), 4, 8 (fast).

Example of monitoring on 4 modules… Test 1: all modules powered Test 2: modules powered one at at time

Example of temperature monitoring on 4 central modules… Speed 1 Speed 4 Speed 8 Speed 1 Test 1: all modules powered Speed 4 Speed 8 Test 2: modules powered one at at time

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 10 C!) A better uniformity is achieved incresing the cooling speed (Tmax –Tmin 4 C)

How cooling speed change the DT/power?

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 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

Example of T monitoring during STAVE test: MODULES 7 -13 TEMPERATURE 7 hours for half stave (source excluded) Test 510237 Test 510803 Test 510864 510803 510237 Cooling flow 510893 510844 510405 Module Test direction 510396

HV off with SURF or with MAC Noise ~400 e!

Then the analysis finds Unconnected bad pixels with this low rows peculiar pattern!

Electrical tests analysis STAVEFLEX Comparison done using the “official” STAVE cuts without cut on HVoff data (as there is the source scan). LOADBURN 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.

Bad pixels Increasing in pre-existing defects New Defect between 4 and 5

M 2 a and M 4 a There after loading: is there anything that can damage that point?

M 5 a 225 81 159 Increasing both in loading and cycling

M 6 A 135 299 320 Increasing mainly in loading