cancel
Showing results for 
Search instead for 
Did you mean: 

LPS Pressure-sensor: model differences and part naming scheme

JHenn.1
Associate

I am looking for "cavity"-type pressure sensors like the LPS27 or LPS33 but I am having a hard time finding out what the differences between the models are. For the stm32f series the online documentation includes a great comparison chart of the different models and I was expecting to find something similar for the pressure sensors.

So far I got:

  • LPS22, LPS25, LPS35: normal, "non-cavity" types (not interesting for me)
  • LPS27HHW: 2.7x2.7mm, 200Hz, low noise, CCLGA10
  • LPS33: 3.3x3.3mm, 75 Hz
    • LPS33K: low noise, CCLGA4 (only I2C, no SPI)
    • LPS33HW: low noise, CCLGA10
    • LPS33W: higher noise, CCLGA10

The price (digikey) for LPS27 and LPS33K is similar, the LPS33HW is a bit cheaper and LPS33W is the cheapest.

Whats the point of the LPS33K, the LPS27 is smaller and better and costs the same?

Are LPS33HW and *W just "budged" options or do they offer any benefits that I missed?

Knowing the naming intentions behind "K", "W", "H" and "HH" would probably help understand the differences better. Is that information somewhere available?

Best regards

2 REPLIES 2
Eleon BORLINI
ST Employee

Hi @JHenn.1​ , you can refer to the pressure sensor product selector on corporate st.com website, where all the details are listed.

>> Whats the point of the LPS33K, the LPS27 is smaller and better and costs the same?

Thanks to its potted gel package (more expensive), the LPS33K device has a high overpressure capability: 20x full scale.

>> Are LPS33HW and *W just "budged" options or do they offer any benefits that I missed?

They differ from the package.

>> Knowing the naming intentions behind "K", "W", "H" and "HH" would probably help understand the differences better. Is that information somewhere available?

I suggest you to check the Quick reference guide, where the meaning of the part number letters are described (H = high performance, W = "waterproof").

you can btw also download the ST Sensors Finder app from your smartphone store and select the application (and the related sensor) that best fits your need

Regards

JHenn.1
Associate

Thank you for your reply.

About the potted gel package: the datasheets show that all sensors (LPS27and LPS33W/HW/K) have a potted gel package. All LPS33 (K,W and HW) are rated to 20x overpressure capability. So I guess the difference is that the LPS27 also has a potted gel package, but a different one that is less protective.

I still would really like to understand the intention behind using a CCLGA4 package for the LPS33K. The sensor has the exactly same physical size as the LPS33W/HW but uses less pins which removes the option to use SPI.