Attendance:
Conny, Philip, Bhavna, Kaz, Alex, Zongde, Xavier, Julian, Nolan, Chris, Lorenzo, Bojan, Angelo
Agenda items:
- Presentation on results for TID
Presentations:
Initial Findings For ePixHR Prototype (Conny)
Lorenzo's notes:
Issues:
- Banding
- Tests that can be done:
- TID: Can test ADC independently with external DAC voltage
- Calibration team: Look at different pixels in the same column, they are connected to the same ADC. See if the missing parts are the same everywhere.
- Calibration/TID: Charge injection scan.
- Banding shows up in Dionisio's data too.
- Tests that can be done:
- Linearity vs rates
- Shift observed in pedestals
- Angelo: suggest to run at higher rate, and optimize there. The fact that the pedestals in LG shift, seems that something is marginal in terms of timing.
- We can see the effect also in the lab
- ToDo:
- TID: figure out the exact history of the calibration, re-check timing and registers.
- Investigate charge injection, can we get close to 5kHz.
- Variation in linearity/switching point
- Lorenzo: there's a ping-pong with 2xS/H channels in between the pixel column and the ADC.
- Discussion of possible issues:
- Offset in Vthr of the pixel
- Offset in the CSA, that gets removed by CDS.
- Difference in S/H gain+offset, but doesn't explain the magnitude.
- Can we use charge injection?
- Can we use ADC Vcalibp to rule out if it's the S/H or the pixel?
- CompEn variation
- See bank structure
- Bojan: due to distribution
- Not too big of an issue in HR?
- Keep an eye out in UHR! Lorenzo: different implementation, we should be good with ~ns skew across whole matrix