1. The transmission line used in a typical PCB consists of conductive traces embedded in or attached to an insulating material, along with one or more reference planes.

2. The conductive traces are generally made from copper, while the dielectric material commonly used is “FR4,” which incorporates glass fiber.

3. The two most common transmission line structures in digital design systems are microstrip and stripline.

4. Microstrip lines can be classified into standard microstrip lines and embedded microstrip lines. The former refers to traces on the outer layer of the PCB, which are directly attached to the dielectric plane and exposed to the air.

5. The latter represents an improvement over the former, as the copper traces are covered with a dielectric material.

6. Stripline, on the other hand, is a transmission line that is surrounded by dielectric materials and positioned between two conductive planes.

7. The key distinction lies in whether the distance between the stripline and the two conductive planes is equal.

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