Posifa Technologies Introduces PVC4001-C MEMS Pirani Vacuum Transducer for Wide-Range Vacuum Measurement

­Posifa Technologies today introduced its new PVC4001-C MEMS Pirani vacuum transducer, the latest device in the company's PVC4000 series. Designed for cost-effective OEM integration, the transducer combines a MEMS thermal conduction sensor, measurement electronics, a microprocessor, and an onboard barometric pressure sensor in an ultra-compact PCB assembly with a connector-terminated wire harness. 

Based on Posifa's second-generation MEMS thermal conduction chip, the PVC4001-C operates on the principle that the thermal conductivity of gases is proportional to vacuum pressure. Its electronics and microprocessor amplify and digitize the sensor signal and provide output via an I²C interface. For applications requiring calibrated output, users can enter up to 10 pairs of calibration points, which are used by a built-in piecewise linearization algorithm. 

The PVC4001-C is designed to deliver stable performance across changing operating conditions. A built-in temperature sensor supports a temperature compensation algorithm to offset changes in thermal conductivity caused by ambient temperature variation. In addition, a pulsed excitation scheme — in which the sensor is heated for about 100 ms and then turned off for one second — helps minimize drift due to self-heating in high vacuum, while also reducing power consumption for battery-powered instruments. 

The device provides a measurement range from 0.001 Torr to 900 Torr (1.3*10-4 kPa to 120 kPa) with a response time of less than 200 ms. Because Pirani vacuum sensors typically lose resolution above 10 Torr, the PVC4001-C adds an onboard barometric pressure sensor that supports measurement from 10 Torr to 760 Torr with 5 % accuracy across that extended range. This combination makes the device especially well-suited for portable digital vacuum gauges and for leak detection in closed systems maintained under primary vacuum, including vacuum-insulated panels. 

Additional features of the PVC4001-C include low power consumption, resistance to contamination, and an operating temperature range of -25 °C to +85 °C. 

More information is available here.