wiki:HV_RevB

HIGH VOLTAGE RevB FULL TEST

Overview: For this test the voltage input of the Filament Supply RevB was connected to the output of the HV Pulser RevB. In this test the HV Pulser was tested at an operating Frequency of 1MHz.

Measurements: The ON, POS, and NEG control signals were measured directly from the PMOD connector on the BASYS 3 FPGA. The same system for measurements on the filament supply was used as Filament Supply RevA 2/7/20.

Results:
HV Pulser RevB output:
http://gauss.bu.edu/svn/tof-system/Gallery/2020-04-13/HV_rise.jpghttp://gauss.bu.edu/svn/tof-system/Gallery/2020-04-13/HV_fall.jpg
In the two images above, both the rise and fall time of the output from the HV Pulser is ~100ns. It is also worth nothing the absence of over and undershoot. The major modification made to the HV Pulser in RevB was adding a diode clamping circuit to the output. This appears to be working properly and preventing the output from over/undershooting as it switches from ground to the supply voltage.
Filament Current Supply RevB output:
http://gauss.bu.edu/svn/tof-system/Gallery/2020-04-13/HV_nogap.jpg http://gauss.bu.edu/svn/tof-system/Gallery/2020-04-13/HV_gap.jpg
In these two images you can see the linear behavior of the Filament Current supply. In the first image there is essentially no voltage gap between the top and bottom of the load, in this state no current is being pushed through the load. In the second image there is a 10V drop across the load. For this test the load was a 10W 10ohm cement resistor. As expected the voltage drop across the load scaled linearly between these two images as the potentiometer was adjusted. The full behavior of the Filament supply is described in more detail in this page
http://gauss.bu.edu/svn/tof-system/Gallery/2020-04-13/Fil_fall.jpg http://gauss.bu.edu/svn/tof-system/Gallery/2020-04-13/Fil_rise.jpg
These two images show the fall and rise behavior of the Filament Current Supply. The Filament Current Supply also has a rise and fall time of ~100ns, this means it doesn't add any delay to the output of the HV Pulser. In these two images it is also visible that there is no relevant delay between the top of the load (the output of the HV Pulser) and the Filament Supply response in the bottom of the load.
Results: These results are good. RevB of the HV Pulser and Filament Supply are both working properly.
Special Note on Drift:
Output drift is still present in RevB of the HV Pulser. This behavior is related to properties specific to the load, not the HV Pulser, and is discussed in full detail on this testing page.

Last modified 2 years ago Last modified on Apr 14, 2020, 11:59:38 AM