Re: Protecting I/Os




"A.D." <isd_mod@xxxxxxxxx> writes:
Witch kind of protections are commonly used for this kind
of sistems, and how are they implemented?

I don't know about commonly, but this is what I'm doing in my current
project (http://www.delorie.com/house/furnace/pcb2/):

Panasonic EXC-CET222U EMI filter (L-C-L module, SMT)

Followed by a Littelfuse SP724AHTP clamping chip.

Then the signal goes into an 0603 star configuration which I can
populate with a variety of other signal-specific discretes (like 1wire
pullups). It's similar to this old schematic, which uses diodes
instead of the clamp chip: http://www.delorie.com/house/furnace/pcb2/io_port.html
(ignore the left side of that schematic)
.