This USB micro B has 6 mounting tabs. If I ground none or only 1 of them, will it ruin the signal? There is a pad for the signal ground that is separate from the mounting tabs.
Fyi USB 2.0 has a max signal rate of 400 Mbps, and an effective payload throughput of up to 35 Mbps, according to Wikipedia.
Is there a general best practice for lazy / layout-confined people to decide how many mounting tabs have to be grounded for a tens-of-megabits connector?
If I only ground one of the tabs, should it be the one closest to the board edge (i.e. to the cable)?
Thanks!
Best Answer
I think normally you don't ground the USB shield on the device side. Instead, you should connect your shield to the chassis/other shielding components, and connect your PCB ground to the USB ground. Between the USB ground and shield you can add a 1Mohm resistor in parallel with a 4.7nF ceramic capacitor.
References:
Cyprus Semiconductor: Common USB Development Mistakes
Atmel: USB Hardware Design Considerations
edit:
did a little more digging, and for higher speed connections it seems like you do tie the shield to ground? I'm not entirely positive about this.
How To connect USB connector shield