Mass Flow Sensors

PVC1000 Series Pirani Vacuum Sensor

The PVC1000 Series of MEMS Pirani Vacuum Sensors offer a breakthrough vacuum measurement solution that enhances miniaturization while delivering ultra-low power consumption, long lifetime, minimal field maintenance, and low cost. Based on the principal that the thermal conductivity of gases is proportional to pressure in the low vacuum range, the Posifa sensors measure minute changes in resistance to a heated element resulting from heat transfer to the surrounding gas.

The heated element consists of a platinum thin-film resistor residing on a thermal insulating membrane. The membrane is suspended over a micro-machined cavity that is 25µm in depth and has a bottom surface that is parallel to the membrane, ensuring precision measurement of heat transfer. Due to the minute volume of the gas measured (i.e. the volume within the cavity), the Posifa sensors deliver ultra-low power consumption and fast response time.

The PVC1000 also provides a reference resistor of the same Thermal Coefficient of Resistence (TCR) as the measurement resistor, residing on the sensor substrate. It can be used by the sensor circuitry for ambient temperature compensation.


  • Ultra low power consumption of less than 5 mW
  • Fast response time of less than 5 mSec
  • Range of 10-3 to 30 Torr
  • Shock resistance to 1,000g
  • Suitable for gas volume as low as 0.1 cm-3
  • Insensitive to mounting orientation
  • Low noise
  • High resolution
  • On-chip temperature sensing
  • Long-term stability
  • Can be cleaned by immersing in solvent, prolonging useful life


  • Analytical instruments
  • Leak detection in any closed system maintained under primary vacuum
  • Semiconductor equipment
  • Vacuum packing machines
  • Portable vacuum gauges
  • Small mechanical systems (e.g. pumping) to achieve specified vacuum levels
  • Low cost vacuum switches to verify vacuum below 1 torr