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ePixUHR-v3 VDDA = 1.4 - Linearity

TID-ID Edge Computing Systems

Pietro King

27th March 2025

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Increasing VDDA Supply

TID-ID Edge Computing Systems

2

We wanted to increase the VDDA supply from 1.3V to 1.4V, to have a higher range for the analog section of the ASIC.

FLG2 measurement from latest beamtime.

Given the gain of 0.023 ADU/keV and baseline of 1150, in this case the max energy we can reach is around 35 MeV.

The target max energy FSR should be ~ 80 MeV

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Optimized values for linearity

TID-ID Edge Computing Systems

3

Starting setting

Optimized settings for linearity

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Optimized values for range

TID-ID Edge Computing Systems

4

Optimized settings for linearity

Optimized settings for range

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FSR with increase range?

TID-ID Edge Computing Systems

5

Using the settings for increased range, I did a charge injection ramp of AutoHGLG2.

The non-linearities of HG do not seem to translate to the LG2 switching point.

With these settings we get a full scale range of about 70 Mev (closer to the 80 MeV.)

(I still have some other LG settings to tweak)

The baseline at HG of AHGLG2 and FHG seems to vary. We need to ask Lorenzo some study on that.