Evo meeting 21.02.2018

Partecipants: De Remigis, Calvo, Grunwald, Kesselkaul, Lai, Olave,Zaunick.

* Agenda: 
-open questions for ToASt design; 
-check for mechanical constraint of the readout size for strip staves and discs; 
-strip flex design.

+ Toast design. A test bench was set up by Jonhatan to simulate the Pasta analogue part, 
with ideal bias circuits.
Some way was found to tune the peaking time: changing a bias current or increasing 
a capacitor (larger area as a drawback).

Hans explain that it is not needed to have a dynamic range up to 50 fC, 
an upper value of 10 MIPs is sufficient. 
To be confimed by Tobias.
He requires to have linearity in the first part of the dynamic range 
(also below 1 FC !! to be verified according to the threshold value)

At present there are not any clear reasons to keep in the Toast 
project the system with the two thresholds, as in the Pasta circuit.

+ Mechanical constraint. If Toast circuit will have a 4.5 x 3.4 mm2 size (as Pasta), 
it looks compatible with the arrays of 11 chips for the staves.
For the discs there is an issue: currently the mechanical drawing foresees a circuit
 with a side toward the strip of only 4.2 mm.
Dirk will verify why the strip disk shows this particular size for the chip and 
pratically when  the drawing was carried out (the date on the drawing indicateds May 2017)

+ Flex design. The study for flex (or rigid flex) PCB for the staves is becoming 
important to understand routing and feasibility way. 
To implement APV25 is not useful due to the size of this chip.
Daniela suggest to take PASTA as reference chips.
It is important to define all the interfaces to have an idea of the tracks to use. 
To do that , it is not only a problem of the ToASt design but also of the MDC.

We will meet next Wednesday.