3h rule
shahabjafari372@gmail.com , 07-26-2022, 05:13 AM
hello every one . in my stackup the h1(distance between signal layer and upper ground) is 3.2 mil and h2(distance between signal layer and downer ground) is 4.2 . if i want to use 3h rule for minimize crosstalk i should use 3h1 or 3h2?
binayak , 07-28-2022, 12:15 AM
Your stripline configuration is more or less symmetric. Both planes will act as return planes. Normally you would take the lesser among h1 and h2.
How wide are your traces ? Normally for 50 ohm configuration:
(a) if edge to edge spacing (s) = trace width (w), we call it tightly coupled
(b) if s = 2w, we call it loosely coupled
(c) if s = 3w or more, we call it uncoupled
PS. Look at Dr. Eric Bogatin's "Signal integrity and power integrity simplified" for more information.
How wide are your traces ? Normally for 50 ohm configuration:
(a) if edge to edge spacing (s) = trace width (w), we call it tightly coupled
(b) if s = 2w, we call it loosely coupled
(c) if s = 3w or more, we call it uncoupled
PS. Look at Dr. Eric Bogatin's "Signal integrity and power integrity simplified" for more information.
robertferanec , 07-29-2022, 07:23 AM
nearest reference plane:
"It is called the 3H rule. You may already be familiar with an implementation of this rule. 3H stands for three times the dielectric thickness or Height in the Z-axis from the signal layer to the nearest reference ground plane."
"It is called the 3H rule. You may already be familiar with an implementation of this rule. 3H stands for three times the dielectric thickness or Height in the Z-axis from the signal layer to the nearest reference ground plane."
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