Printed circuit boards (pcb) are conductive paths located on an insulating substrate with the role of connection between different electronic components.
The term "controlled impedance" refers to the electrical interconnection paths between electronic components that present a constant impedance when propagating signals.
The impedance depends on the path geometry and the electrical permittivity of the substrate.
Stack-up printed circuit boards 4 layers
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Layer Top |
Stack-up printed circuit boards 6 layers
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Layer Top |
paths, pads Controlled impedance for connections, metallized holes (vias) for passing connections between layers of copper as solid conductive areas for electromagnetic shielding or other purposes. Each of the conductive layers is designed with copper tracks (similar to wires on a flat surface) that provide electrical connections on that conductive
of copper on both sides of an insulating board), or multi-layered (outer and inner layers of copper Controlled impedance alternating with insulating layers). Among the multi-layer PCBs, the most common are the four-layer ones. The four-layer board has many more routing options in the internal layers compared
be larger than the signal paths. In a multi-layer board, impedance Controlled an internal layer may be mostly solid copper to act as a ground plane for shielding and power return. For microwave printed circuits, transmission lines can be laid out in a planar form, such as stripline or microstrip, with dimensions carefully
