Test beam requirements
Data Rates
Per these slides:
- Event rates \~10k events in 4s bursts (56 seconds of silence). Need
to either:
- buffer events in FPGA memory; send to PC after one “run”;
- OR: careful streaming of data to PC continuously.
// parameters
double occupancy = 0.1;
float time = 4;
int events = 10000;
int word_size = 64;
// calculations
float mean_packet_size = 64*2 + 64*occupancy*256;
float dump_size = events * mean_packet_size;
float data_rate = dump_size / time;
printf("@ %3.1f%% Occupancy: dump size = %f Mb / %2.1f s = %f Mbps", occupancy*100, dump_size/1E6, time, data_rate/1E6);
@ 10.0% Occupancy: dump size = 17.664000 Mb / 4.0 s = 4.416000 Mbps
Clock Synchronization
Clock signal also must be distributed to oscilloscope time reference.
External Trigger
An NIM -> CMOS / LVDS converter board is being developed to connect the NIM trigger to the KCU105. The KCU105 has an 8x oversampling trigger input, requiring a minimum pulse width of 3.125 ns to receive the external trigger.
Module Requirements
Initial testing: build simple module PCB “v2”
- Allow operation with 1-2 ETROC2 and 1 LGAD
- Compatible with beta testing (sensor offset from RB)
- Transition to bump-bonded system later, eventually 4x ETROC2 on realistic module
- Need all sensor/chips to be independent (e.g switches) bad chip/sensor can’t kill module
Mechanics
- Cold box