Answers:
1. You compensate by varying the line width
of the trace. You need an impedance calculator to get the values.
2. I'm familiar with designs with the
laminate thickness as low as 3 mils. I'm sure the fabricators on this forum
have a better answer.
David Ricketts
Pertek Engineering
Voice:
949-475-4485
Fax: 949-475-4493
----Original Message-----
From: TechNet
[mailto:[log in to unmask]]On Behalf Of Sefika Ozkal
Sent: Friday,
October 11, 2002 5:35 AM
To: [log in to unmask]
Subject: [TN]
Thickness Problem
Hi,
If we have a PCB with signal layers whose thicknesses
are 6, 8, 10,12 mils, how can compansate the impedance differences? To achieve
the impedance requirements of a design can you offer some
solutions?
What can be the minimum thickness of the laminate
between the VCC and GND planes where the laminate can be FR4
or?
Sefika Ozkal
Electronics
Engineer
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