Programmable System-on-Chip (PSoC) Embedded Readout Designs for Liquid Helium Level Sensors.

This article reports the development of programmable system-on-chip (PSoC)-based embedded readout designs for liquid helium level sensors using resistive liquid vapor discriminators. The system has been built for the measurement of liquid helium level in a concave-bottomed, helmet-shaped, fiber-reinforced plastic cryostat for magnetoencephalography. This design incorporates three carbon resistors as cost-effective sensors, which are mounted at desired heights inside the cryostat and were used to infer the liquid helium level by measuring their temperature-dependent resistance.

PSoC-based embedded design and quartz tuning fork for low-temperature measurement system design.

This article describes a commercial quartz tuning fork (QTF), 8 mm in height by 3 mm in diameter, holding a two-terminal electronic component with a nominal frequency of 32.768 kHz and 12.5 pF typical load capacitance packed in a vacuum-sealed metal container, which has been used as a sensor for low-temperature measurement with good sensitivity, repeatability, and reliability.