CSA voltage limit

The notebook currently sets the CSA voltage limits to 0.3V, which is too high and leads to non-linearity and saturation.

The CSA should be kept to <0.25V.

In UP3423, we discarded data with pixel values above 435, with a dark pedestal of 65, so a range of 370. The gain was: https://rtd.xfel.eu/docs/dssc-operation-manual/en/latest/_downloads/d9a350cb4d36176af7fb90b386cceb62/GenConf_TG0.4284_nG186_trimm_f2.25_intgr150-notebook_output.txt

which gives a CSA voltage of 0.21V.

Changing the CSA_Vlim from 0.3 to 0.25 changes the CSA capacitor from 180pF to 240pF with the same input settings in the notebook.