1. Alternative FEE electronics for FIT.
Evgeny Usenko, INR RAS

2. Alternative LE, CFD, TOT FEE - structure.
Analog part
DC coupled structure,
Offset & temperature cancellation,
Variable gain amplification stage,
15ns deviation width TOT solution.
Digital part
Advanced FPGA – Lattice license,
Signals integrity,
Internal FPGA SPI protocol for full analog part control,
Internal FPGA test generator and test signal distributions,
Internal FPGA DAC’s for fine TOT and CFD and any parts controlling
Interface part
Electronics and optical combine OR&Vertex solution,
Standard FEE to TRB3 digital communications,
Common Power Supply solution for FEE+TRB.
Two by one DAQ and Slow Control board

3. LE, CFD, TOT front-end structure.
Common 32-channel FEE board for combining analog and digital solution
Analog 32-channel prototype
FPGA Lattice
Read-out
leading
trailing
TOT discrim.
trailing
LE+TOT LE
Signal logic:
combining,
stretchers,
other,
signals
distributing.
Leading edge discrim.
TOT lead
Zero+TOT
Zero
Crossing zero discrim.
Interface logic:
SPI controller,
DAC’s,
Test generator,
analog controlling.
Control lines
SPI

4. CFD&TOT simulation for 25ns bunch. DC coupled structure.
CFD and TOT method simulation for 25ns bunch versus recovery time

5. TOT width vs. amplitude and accuracy.
HADES TRB TOF AddOn charge vs. width accuracy.
Average error is <0.4% on (2-200)xThreshold range
Shapers probes

6. TOT shaper simulation for 25ns pulse distance. DC coupled.
Amplitude 6V
Amplitude 8V and 20mV

7. Optical decision for FIT fast trigger.
ALICE R&D optical timing fan-out experience at 2004.
Use optical fan-out as fan-in for realize OR function.
Probe window of timing resolution 12,5ps (sigma)

8. Summary. Alternative Front-end electronics eliminates ADС.
2. Simplified FEE channel include just CFD, LE and TOT functions.
Simple switching to different amplitude range mode by use Leading and Trailing edges TOT options
Separation for FEE and Read-out.
Fully DC-coupled schematic structure for provide 25ns and dynamic range FIT requirements.
Use electronic-optical decision for fast trigger solution.
The software (remote) methods of CFD+TOT calibration.

9. Thank you for your attention. The end?