Frequently Asked Questions

Frequently asked questions about CMOSens® differential pressure sensors

1. Can CMOSens® differential pressure sensors also be used with gases other than air?

2. Can CMOSens® differential pressure sensors be used with inflammable gases?

3. What is the long term stability of the CMOSens® differential pressure technology?

4. Can the CMOSens® differential pressure sensor also be used with liquids?





1. Can CMOSens® differential pressure sensors also be used with gases other than air?

CMOSens® differential pressure sensors are by default calibrated with dry air. Other gases scale the signal and generate a slight offset. For each type of gas, this effect has to be considered.


2. Can CMOSens® differential pressure sensors be used with inflammable gases?

CMOSens® differential pressure meters are wether designed nor qualified for explosive environments. But customers have been known to use them successfully (without guarantee by Sensirion) with flammable gases such as CH4, C2H6, C3H8 and H2. The sensor membrane can reach a temperature of about 50°C above room temperature on less than 1mm2. The heating power is 8mW.


3. What is the long-term stability of the CMOSens® differential pressure technology?

Sensirion has carried out extensive "accelerated ageing tests". Among them are international standard tests like:

• JEDEC JESD22-A104-A (Temp:125°C and -40°C, 1'000 cycles, retention period 20 minutes per step, total 14 days)
  
  
• JEDEC JESD22-A101-B (85°C/85% RH/1000h)
  
  
• DIN-50021ss (salt water spray test)
  
  
• JEDEC JESD22-A110-B (125°C/85% RH/230 kPa/96 h)
  
  
• IEC 68-2-6 (DIN 60068-2-6) (Vibrations: 10 ms-2/25-2000 Hz)

Some other tests proved the offset drift to remain below 0.1 Pa / year.


4. Can the CMOSens® differential pressure sensor also be used with liquids?

No, it can only be used with gases.