Hello, I need a replacement equivalent for DigiKey Part Number 27920-ND
It is a 0-100% humidity sensor. If there is a replacement for this item would be appreciated. This item is listed as obsolete and will require replacing my entire control board and operating system if there is no equivalent
Thanks for your time.
I am sorry to say that I am not seeing an option that would be a direct replacement for 27920 (27920-ND).
The below link shows the items I had found that have the same output.
But the power supply is different.
Humidity, Moisture Sensors | Electronic Components Distributor DigiKey
The below link shows items that have the correct power supply, but the output is different.
Humidity, Moisture Sensors | Electronic Components Distributor DigiKey
Hi sd.sword,
Welcome to the TechForum.
Unfortunately, there is no direct replacement for this part. The part’s OEM part number was HS1101, from manufacturer Humirel, which is now part of TE Connectivity Measurement Specialties.
It is a capacitive-type humidity sensor, so the most similar products would be these. With any of these, one would probably, at a minimum, have to change values on some of the passive components used with it to get the same output response, and one may not be able to adjust them enough to get the same output over the entire humidity range.
If you are producing a PWM output from your circuitry and you are reading this with a microcontroller or similar, then one may be able to use the same passive components and just alter the code to compensate for the different output characteristic of your alternate capacitive humidity sensor.
Another possible option, at least for the near-term, would be the HPP808H031. This is a small circuit board which uses the HT1101 and outputs a frequency based on humidity level. It probably uses the same circuitry that your board does, so it could possibly replace all of that circuitry and feed the output to what ever takes that output in your design.
HPP808H031
As I stated, it uses the same HT1101, so I would not be surprised if this goes obsolete sometime soon as well, but we currently have more than 600 pieces in stock.
Beyond this, you would probably have to do a complete redesign, though, if you are feeding the output into a microcontroller, the hardware redesign may be fairly minimal, but would require code changes to adjust for the type of interface (analog voltage, PWM, I2C, etc.) required for the alternate sensor.
Thanks for the information. I will at some point need to move into the truly digital control world and away from the analog controller.
Appreciate your time and response, I will look into your recommendations further.
Scott
