03-14-2022 11:29 PM
We are considering waterproofing a small module that contains an IMU for a wearable application that must survive laundering, including extended and repeated full submersion in liquid. We are considering potting, or a conformal coating over the PCB inside a waterproof enclosure. The module has to survive storage at temperatures as low as -20C. Advice on handling the thermal stresses due to CTE mismatches between a potting compound or conformal coating and the IMU package mounted on a PCB, advice on application of the coatings to avoid damage to the chip, etc are most welcome. Are there any other suggestions on offer, other than the guidance to avoid only partially covering the IMU with resin?
03-22-2022 10:57 AM
Hi pish,
Our previous customers used Gore's waterproof nano membrane.
03-23-2022 07:31 PM
A review of Gore's offerings and a discussion with Gore technical sales has led us to the conclusion that Gore's membranes are not appropriate for our application. We would like to revisit the possibility of potting with a resin that fully covers the IMU. We are now focusing on the BHI260AP. Its handling notes say that only partially covering the IMU with resin is prohibited, leaving open the option of covering it fully. We'd like some confirmation that that may be OK.
03-24-2022 03:01 AM
Hi pish,
The reason why resin material is not recommended is that it has an impact on stress. You can consult different waterproof material manufacturers as long as you confirm that it will not produce large stress.