Speaker
Description
At CERN, for the High-Luminosity upgrade of the Large Hadron Collider (LHC), the cryogenics instrumentation team will produce 2,000 electronic cards to support 1,800 new instrumentation channels. These cards will integrate with the LHC’s existing infrastructure of 10,000 transducer cards and are therefore designed to be radiation tolerant. This paper describes the results of two irradiation test campaigns conducted at CERN’s CHARM facility in 2023 and 2024, aimed at validating the performance and resilience of the new electronics in a representative radiation environment.
Summary (500 words)
At CERN, for the High-Luminosity upgrade of the Large Hadron Collider (LHC), the cryogenic instrumentation team will produce 2,000 electronic cards to instrument 1,800 new channels. These cards will integrate into the LHC’s existing infrastructure of 10,000 transducer cards, designed to be radiation tolerant. To validate the tolerance of the selected components and designs, we conducted irradiation tests at CERN’s CHARM facility in 2023 and 2024. The CHARM facility features a mixed radiation field able to replicate diverse radiation environments such as space, the atmosphere, and accelerator facilities.
In the test campaign of 2023, we used two experimental setups to test 10 discrete components and two prototype cards. The components included PNP/NPN transistors, NMOS/PMOS MOSFETs, a DC/DC converter, an operational amplifier (Op-amp), a Thyristor Surge Suppressor (TSS), a PTC fuse, and two voltage regulators. The prototype cards consisted of a Digital Input Output (DIDO) card, and an Electrical Heater (EH) card tested in both AC mode and ON/OFF DC PWM mode. Additionally, a Wien Oscillator circuit using a JFET, an Op-amp, low-leakage capacitors, and diodes were evaluated. These setups were irradiated up to a Total Ionizing Dose (TID) of 1,740 Gy.
In the 2024 test campaign, five setups were employed to evaluate 15 discrete components, three prototype electronic cards, an add-on auto reset module for our communication cards using the WorldFIP fieldbus protocol, a communication card using the NanoFIP module (a variant of the WorldFIP fieldbus developed by CERN), a tray with ventilator units, and two additional prototype cards. The components tested included an oscillator, an ADC, an op-amp, a JFET, a DC/DC converter, a voltage reference, three level translators, three linear voltage regulators, an isolator, and two switching regulators. The DIDO and EH prototype cards were tested again, incorporating improvements related to component radiation tolerance. These setups were irradiated up to a TID of 1,476 Gy.
For the FPGAs used in our designs, the paper compares results from earlier irradiation campaigns (2016-2018) using the Smartfusion® 2 FPGA with those of the 2023 and 2024 using the Igloo® 2 FPGA. The comparison includes TID, Single Event Latchups (SELs), and Single Event Functional Interrupts (SEFIs). The most recent FPGA configurations achieved zero SELs and SEFIs, demonstrating significant robustness under irradiation with cross-sections lower than 6.85 x 10-14 cm2/device for high-energy hadrons (HEH, E > 20 MeV). FPGA TID failure thresholds were typically above 600 Gy, with some devices reaching up to 850 Gy, particularly in designs with sufficient timing slack.
Furthermore, in the 2024 campaign, we enabled the High-Performance Memory Subsystem (HPMS) of the FPGAs to read data from the Embedded Nonvolatile Memory (eNVM). This configuration was tested, with the FPGAs able to correctly access stored data up to the end of their TID life.
These irradiation campaigns are part of a comprehensive qualification program for the development of radiation-tolerant electronics for the HL-LHC cryogenic systems. The data validate the selected technologies and design approaches, supporting the reliable production of the electronic cards required for deployment in the LHC radiation environment.
