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 |
the printed circuit, called serigraphy or silkscreen for short, is done on the top layer of the PCB and has the role of a reference indicator for the components Controlled impedance on the PCB. Graphics and text on a circuit board's PCB are usually printed with a non-conductive permanent epoxy ink. The color
care must be taken in designing the tracks to match the impedance of the upstream and downstream components. The longer the route or the higher the frequency, the better adaptation is required. When producing the printed circuit with controlled impedance, the impedance will be controlled by acting on the dimensions of the tracks impedance Controlled and
and better power supply decoupling. In multilayer boards, layers of material are laminated together in an alternating sandwich: copper, substrate, copper, substrate, copper, etc.; each layer of copper is etched and any internal sleepers (which will not extend to both outer surfaces of the finished multilayer board) are plated Controlled impedance before the layers are laminated
