[Arm-netbook] HDMI High-Frequency Layout: Recommendations--Taper

[Richard Wilbur]

On Sun, Dec 17, 2017 at 11:34 PM, Luke Kenneth Casson Leighton
<lkcl at lkcl.net> wrote:
> On Mon, Dec 18, 2017 at 6:31 AM, Richard Wilbur
> <richard.wilbur at gmail.com> wrote:
>> 1.  Ground keepout under whole ESD component(s) on adjacent reference
>> ground plane (layer 2 for ESD on layer 1, layer 5 for ESD on layer 6),
>> ground fill on deeper layer (layer 3 for ESD on layer 1, layer 4 for
>> ESD on layer 6).  Ground fills connected as always using vias (some
>> probably already adjacent).
>> 2.  Ground keepouts under just high-frequency signal pads of ESD
>> components on adjacent reference ground plane (layer 2 for ESD on
>> layer 1, layer 5 for ESD on layer 6).
>>
>> Clear as mud?
>
>  clear... except which one to actually deploy :)

Well, I read about #2 in the TI High-Speed Layout but I like #1 better
because we have high-frequency signals in parallel on both sides of
the board and I'd feel better because I expect less cross-talk with
#1.  #1 is a hybrid where we double the distance to the reference
ground plane but still have ground shield between high-frequency
signals that would otherwise want to radiate/couple.