RAK16001 extreme sensitivity to electrostatic shock

[ArneJoris]

The RAK16001 analog-digital converter seems extremely sensitive to electrostatic shock; I have gone through three of them in two days, whilst waring a ground strap.

After being ‘zapped’, the RAK16001 will start reporting around 0.23 volt on each of the 8 channels.

We haven’t had any raspberry PIs or other WisBlock components go bad because of electrostatic shock; do we need to take any extra precautions for RAK16001, or is there a recommended circuit we should use to connect to the input channel leads to avoid damage ?

[carlrowan]

Hi @ArneJoris ,

I am not using RAK16001 much but if you suspect ESD issues, TVS ESD protection diodes can help. This is not included in the module so probably extra care is needed if your area is prone to ESD. Analog input are subject more to this issues compared to digital ones.

[ArneJoris]

Thanks @carlrowan , I added some TVS diodes to redirect the static electricity. With relative humidity around 25%, we get zapped continuously in winter!

I measured the internal reference voltage to be 2.58 V, and averaging four consecutive single ended samples gives me a fairly stable and accurate measurement.