must be taken in designing the tracks to match the impedance cablaje imprimate 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
ground plane for shielding and power return. For microwave printed circuits, transmission lines can be laid out in a planar form, cablaje imprimate such as stripline or microstrip, with dimensions carefully controlled to ensure consistent impedance. In RF and fast switching circuits, the inductance and capacitance of the printed circuit board
with additional internal layers of copper and imprimate cablaje insulation are called multilayer. PCBs can be single-sided (one layer of copper), double-sided (two layers of copper on both sides of an insulating board), or multi-layered (outer and inner layers of copper alternating with insulating layers). Among the multi-layer PCBs, the most