I am looking for the units of ESD protection. At which magnitude in numbers we can say that the device has good ESD protection ?
First, and key to it all, is that "we" don't always
get to say what's good (enough).
Manufactures internally will insist their products
can make it through the manufacturing line
all the way without creating yield fallout or
a population of "walking wounded" shipped
out, to become field returns later. This also
means "good enough" for customer IQC (if any).
Users of the parts similarly want their TV set
or whatever, to survive Stupid Consumer Abuse
testing at a bazillion different abuse-sites so
they don't eat a sub-bazillion warranty returns.
These will impose a higher standard on those
parts than simple "handling ESD" (HBM, MM).
Sometimes this even becomes a datasheet
and marketing call-out if it's advantageous.
See stuff like 8kV (with a newer-than-I-paid-
attention-to JEDEC or IEC spec) on things like
HDMI channel front end parts, anything that's
exposed to a connector pin).
Any and all of those parties, mentioned and
unmentioned, are all to happy to tell you to
go do stuff. And to demand more than they
really, absolutely need, which validating is on
you.