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Each trace consists of a flat, narrow part of the copper foil that remains after etching. The resistance, determined by width and thickness, of the traces must be sufficiently low for the current the conductor will carry. Power and ground traces may need to be wider than signal traces. In a multi-layer board one entire layer may be mostly solid copper to act as a ground plane for shielding and power return. For microwave circuits, transmission lines can be laid out in the form of stripline and microstrip with carefully controlled dimensions to assure a consistent impedance. In radio-frequency and fast switching circuits the inductance and capacitance of the printed circuit board conductors become significant circuit elements, usually undesired; but they can be used as a deliberate part of the circuit design, obviating the need for additional discrete components.

What process is a trace left over from?
etching
Läs detta och besvara frågan Varje spår består av en platt, smal del av kopparfolien som återstår efter etsning. Spårens motstånd, som bestäms av bredd och tjocklek, måste vara tillräckligt lågt för den ström ledaren ska bära. Kraft och markspår kan behöva vara bredare än signalspår. I en flerskiktstavla kan ett helt lager vara mestadels fast koppar för att fungera som ett markplan för avskärmning och kraftåtergång. För mikrovågskretsar kan transmissionsledningarna läggas ut i form av stripline och microstrip med noggrant kontrollerade dimensioner för att säkerställa en konsekvent impedans. I radiofrekvens- och snabbkopplingskretsar blir de tryckta kretskortsledarnas induktans och kapacitans betydande kretselement, vanligen oönskade; men de kan användas som en avsiktlig del av kretsens konstruktion, vilket undanröjer behovet av ytterligare diskreta komponenter. Vilken process är ett spår kvar från?
Read this and answer the question Each trail consists of a flat, narrow portion of the copper foil remaining after etching. The track resistance, determined by width and thickness, must be low enough for the current the conductor is to carry. Power and ground tracks may need to be wider than signal tracks. In a multi-layer board, a full layer may be mostly solid copper to serve as a ground plane for shielding and power return. For microwave circuits, the transmission lines can be laid out in the form of stripline and microstrip with carefully controlled dimensions to ensure a consistent impedance. In radio frequency and quick-connector circuits, the inductance and capacitance of printed circuit board conductors become significant circuit elements, usually undesirable; but they can be used as a deliberate part of the circuit design, eliminating the need for additional discrete components. What process is one trace left from?
etsning
etching