Rajeev Ranjan E.C.E

Not to be confused with printed electronics .
"Printed circuit" redirects here. For the
defunct company, see Printed Circuit
Corporation .
Part of a 1983 Sinclair ZX Spectrum
computer board; a populated PCB, showing
the conductive traces, vias (the through-
hole paths to the other surface), and some
mounted electronic components
A printed circuit board (PCB) mechanically
supports and electrically connects electronic
components using conductive tracks, pads and
other features etched from copper sheets
laminated onto a non-conductive substrate .
PCBs can be single sided (one copper layer),
double sided (two copper layers) or multi-layer .
Conductors on different layers are connected
with plated-through holes called vias .
Advanced PCBs may contain components -
capacitors, resistors or active devices -
embedded in the substrate.
Printed circuit boards are used in all but the
simplest electronic products. Alternatives to
PCBs include wire wrap and point-to-point
construction . PCBs require the additional
design effort to lay out the circuit but
manufacturing and assembly can be
automated. Manufacturing circuits with PCBs
is cheaper and faster than with other wiring
methods as components are mounted and
wired with one single part. Furthermore,
operator wiring errors are eliminated.
When the board has only copper connections
and no embedded components it is more
correctly called a printed wiring board ( PWB)
or etched wiring board . Although more
accurate, the term printed wiring board has
fallen into disuse. A PCB populated with
electronic components is called a printed
circuit assembly ( PCA ), printed circuit board
assembly or PCB assembly ( PCBA). The IPC
preferred term for assembled boards is circuit
card assembly ( CCA ), [1] for assembled
backplanes it is backplane assemblies . The
term PCB is used informally both for bare and
assembled boards.