Hi,

sn00p Quote:
The fix was easy, but it took a while to figure out what was going on.

Response:
That's why I gave the detail that I did, to help others. There's nothin' worse than EMI Pain...

I also noticed that the schematic he referred to has very little decoupling too. It would benefit from a 10uF capacitor on the USB power side of the inductor. A lot of designers don't consider the Power Distribution System (PDS) and where currents are sourced or returned. Istvan Novak (Sun Microsystems) has a good understanding of it and his website is a good reference for PDS design.


sn00p Quote:
Was usb designed by sadists?

Response:
Yes <sad grin>


Ross
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In SI, a little termination and attention to layout goes a long way. In EMC, without SI, you'll spend 80% of the effort on the last 3dB.