Dante and Gustavo are simulating (160 SiPMs into single channel is change to Gustavo) .. differential current mode requires pre-amplifier (which can be summing node of active ganging).
160 SiPM ⇒ 2 OpAmps ⇒ 2 channel ADC
20 x 4 ⇒ OpAmp ⇒ 1 channel
Gustavo says we know 12 channels into a single OpAmp is fine
So 8 branches is expected to be fine into single OpAmp.
Developing board with each branch having 20 SiPMs. (similar to what we did 2 years ago)
Gustavo wants to move OpAmp close to the ADC
For analog, Gustavo says you can do two stage if you want but bandwidth and dynamic range may be hard. Gain of 1 is unstable in the cold.
1 min to 2000 max pe (is more difficult with two stage.. But there are stability problems)
Bill P wants to know how we get to 4 analog transmitters for 640 SiPMs 4 tiles
Power to one tile of 160 SiPMs .. Flavio says one copper bias.
Alan P and SMU digital Tx update.
Ryan R had to leave at hour mark