Looking for appropriate forum/mailing list for ESD and EMC questions

Dear Experts,
I have been a long time follower of the mailing list and I have thoroughly
enjoyed reading about the expert opinions, and have learned considerably.

Now I have some questions, but it is not directly SI related, so I would
appreciated very much if some one could point me to a forum as high quality
as this for the relevant topics.

Topic 1: ESD

I have a board with 16" of test traces in the inner layers between ground
plane terminating in SMA connectors. I null tested the SMA cable to scope
with 50 ohm SMA terminator and it did not pick up any noise from a +4kV ESD
gun contact discharge to the Horizontal Coupling Plane at a distance less
than 2 feet away. But it picked up several hundred mV of noise when
connected to the test traces with SMA 50 ohm termination.

My questions are:
1) Is this level of noise pick up expected?
2) Will Faraday cage shielding help? My doubt is that if the coupling is
magnetic and nearly 1 GHz, Faraday cage might not help. But if truly so,
then how can anything with a CPU be protected at all?

Topic 2: FCC EMC

I have an HDMI Tx IC that uses only a 27 MHz crystal with internal
oscillator. But it internally multiplies the clock to GHz range and sends
data through a shielded cable at 3 Gbps. For FCC compliance for
unintentional radiator, will I have to scan to 5 x 3 GHz = 15 GHz?


Thank you very much, experts.

Alfred Lee

alfred1520list 4 years 11 months 21 days

0 answers

The best answer

You can select the best answer for current question!