Embedded Microstrip Trace
CHAPTER 44.9 Embedded Microstrip Trace
The copper trace on the surface of the PCB is often covered by a solder mask layer. The PCB traces are, therefore, not in direct contact with the air with dielectric constant 1. This structure is represented as an Embedded Microstrip as shown in the figure below.
Figure 4.7 - Embedded Microstrip
Because of the increase in the effective dielectric constant, the capacitance per unit length of the embedded microstrip structure is greater than the corresponding non embedded microstrip structure.
4.10 Stripline Trace
A stripline trace is embedded between two power planes.
Online calculators can be used to find the capacitance per unit length. Here are two of the links that use this formula to calculate the capacitance per unit length
Calculator for Capacitance per unit length 1
Calculator for Capacitance per unit length 2
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