On Mon, Dec 18, 2017 at 6:03 AM, Richard Wilbur <[email protected]> wrote:
> So it might be easier to just put a ground keepout on layer 2 under > the ESD component on layer 1 and a corresponding ground fill on layer > 3. Likewise a ground keepout on layer 5 under the ESD component(s) on > layer 6 and a corresponding ground fill on layer 4. yehyeh. ah.... do you mean the *whole* component? conflicts with putting keepout(s) under individual pads... > I was recommending just under the ESD pads specifically for the > high-frequency differential signals. conflicts with words above about "GND keepout under ESD components"... >> >>> Likewise with the connector, I would put a ground keep out under the >>> lands on layer 2 (probably best to just draw a keepout under the whole >>> connector on layer 2) >> >> including for the HSCL, HHPD and even the GND pads? of course there's >> VIAs connecting the tracks in between the diff-pairs > > Wouldn't have to I suppose but the idea is to move the ground further > away from the high-frequency pads to reduce the capacitive coupling > thus increasing the impedance. Thus I think it's probably best to > extend the layer 2 keepout under the whole connector. got it. l. _______________________________________________ arm-netbook mailing list [email protected] http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook Send large attachments to [email protected]
