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topic:engineering:cryogenics:electronics

Low temperature electronics

Collected tips

Nikolai Beev/CERN (Source)

  • Bipolar Si transistors and diodes don't work.
  • Shottky diodes usually work, their forward voltage drop increases
  • LEDs work, also with increased Vf and brightness
  • Most signal MOSFETs work. Many CMOS ICs work as well, including digital logic and a few op amps
  • Some SiGe transistors work and even become better (lower noise, higher gain and bandwidth). But they are difficult to tame and prone to oscillations in the GHz frequencies.
  • Small signal relays usually work. I've used plenty of latching Omron relays for switching things in the cold.
  • Thin film resistors with tempco of 25 ppm/K or lower work fine.
  • Thick-film resistors made of RuO2 go up in resistance and can be used for thermometry.
  • From the ceramic capacitors, only NP0 don't freeze out. Forget about high-value X7R and the kind.
  • Plastic capacitors usually work fine. Panasonic ECPU are a good SMD series with PPS dielectric - others should be fine too (PET or PP).
  • Forget about electrolytic capacitors. Only Niobium ones work somehow, but poorly.
  • Most ferromagnetic materials freeze out. Some Vitrovac tape-wound cores don't. Interestingly, circulators work too, though no one knows exactly what kind of ferrite material they use (-:
  • Standard FR4 PCB material works fine.
  • Tin/lead solder works fine, but lead-free solder likely also will work.
  • PhD Thesis - Cern - \cite{Kaltenbacher:2013}
  • PhD Thesis - Delft - The beginning chapters are quite useful as reference. \cite{Homulle:2019}
  • Different electronic materials at 4K \cite{Fink.Fabing.ea:2008}
  • Commercial electronics for cryogenic use. \cite{Buchanan.Benford.ea:2012}
topic/engineering/cryogenics/electronics.txt · Last modified: by samuel