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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Wilson__ on October 15, 2024, 05:20:59 pm

Title: Do you use anti ESD zener diode on magnetc snap on circuit?
Post by: Wilson__ on October 15, 2024, 05:20:59 pm

Smart watch and fitbits use contact points on casing and charging cable is magnetic snap on.

Contact points are touching directly with human body.

Do you use anti ESD protection circuit on these pins?

Many thanks

Title: Re: Do you use anti ESD zener diode on magnetc snap on circuit?
Post by: Salitronic on October 16, 2024, 08:24:16 am

If this is for a commercial product it will need to pass ESD testing and all user-accessible inputs/contacts will be subjected to a contact discharge test.
If there is a relatively large capacitance behind those contacts you might get away without an ESD protection diode (though I would still put one in), but otherwise you almost certainly need an ESD protection diode. The ESD diode should be placed as close as possible to the external input/contact and a series resistor should be added between the ESD diode and the rest of the circuit to protect it from the high clamping voltage of the ESD diode.