Next generation rad-hard links Carmelo Scarcella EP-ESE-BE
Outline Versatile link overview Rad-hard transceiver – VTRx Timeline “Build of material” Specs Conclusions
Versatile link Parameter Value Units Max Bit Rate 4.8 Gbps Wavelength Optical Rx Optical Tx Optical Tx Optical Rx Front-end Radiation hard Transceiver - VTRx Passive optics Optical fibers And connectors Back-end Custom off-the-shelf transceiver Parameter Value Units Max Bit Rate 4.8 Gbps Wavelength 1310 nm Total ionizing dose (TID) 10 kGy Fluence 5 · 1014 n/cm2 MeV neutrons
Single-mode Versatile Link Transceiver - VTRx Laser Diode TOSA TX PIN + TIA ROSA RX Laser Driver connector edge I2C PCB InGaAs Photodiode Transimpedance amplifier (TIA) Laser Laser driver Mechanical latch and PCB Beam Instrumentation Group orders BE-BI-BL: 500 modules BE-BI-QP: 500 modules More modules are needed during CERN LS3!!!
Project time-schedule Single-mode VTRx development Single-mode VTRx installation
Receiver Optical Sub-assembly - ROSA InGaAs Photodiode Off-the-shelf component Transimpedance amplifier (GBTIA) Custom rad-hard ASIC Assembling of ROSAs for first generation of Single-Mode VTRx is ongoing Add parts for the new generation of VTRx to this production stage? Laser Diode TOSA TX PIN + TIA ROSA RX Laser Driver connector edge I2C PCB
Transmitter Optical Sub-assembly - TOSA Laser diode Obsolete part Need to identify a replacement Market survey has been done and test samples procured Radiation tolerance is the main selection parameter Laser Diode TOSA TX PIN + TIA ROSA RX Laser Driver connector edge I2C PCB
Laser driver Custom rad-hard ASIC – GBLD V4.2 Max data rate of 5 Gbps Limiting factor for the link speed! Ibias = 2 ÷ 43 mA Imodulation = 4 ÷ 24 mA Able to drive edge-emitting Lasers and VCSELs Next Laser driver generation will drive VCSELs only lower current and data rate 10 Gbps Laser Diode TOSA TX PIN + TIA ROSA RX Laser Driver connector edge I2C PCB
Mechanical latch and PCB Injection molding mechanical latch custom design based on TOSA and ROSA mechanical constrains a new design and mold might be needed to suit the new TOSA Electronic board might need revision
Link specs Radiation tolerance? Temperature range? Max link length & breakpoint number? Magnetic field? Input needed from Beam Instrumentation Group! Rough estimation for number of modules?
To do list Select a new LASER die Modify latch and PCB Procurement of photodiodes before they became obsolete Availability of TIAs and Laser drivers
Conclusions Project analysis Single-mode TOSAs procured from different suppliers Irradiation test planned for April 2017 Laser diode functional evaluation ongoing Specs to be defined based on Beam Instrumentation Group requirements