Designing of printed circuit board is not as easy as it may
seem to be! Therefore, number of rules & regulations are followed for
designing the boards by the PCB design companies in order to get the respective
layouts-as quality can make a drastic difference. Following are some printed
board design rules:
·
Single
sided PCB: Circuit boards can be designed in two forms single sided and double
sided. But as far as possible, companies prefer single sided because circuitry
can be routed easily with the use of jumpers on these boards, as compared to
the double sided boards. Moreover, double sheets also causes price hike of 1 to
2 times more than single sided boards. Hence, so far companies prefer these as
the cheapest PCB for making out consumer products.
·
Panelisation of
PCB: Panelisation plays major role in cutting the cost of PCB fabrication. This
is because of the prominent fact that it helps to save up 80% to 90% of PCB
lamination. However, if not done so, wastage up to50 % would occur which is not
at all worthwhile. Therefore, usually manufacturers prefer standard sizes that
comprise of dimension 40 inches * 48 inches.
·
Small size: The
fundamental rule of printed circuit board design is to use small size of board during
its layout, in order to have best output of fabrication. Few points taken into
considerations in relation to size are spacing, track width and various other
constraints.
·
Silkscreen:
It should be either eliminated or minimized up to a great extend because if
used, later it would cause difficulty in trouble shooting. Hence, PCB companies
itself or while recommending make sure that if they are using silkscreen on top
overlay then they won’t be using it again on bottom overlay.
·
Reduce
number of holes: The basic role when it comes to drilling is keeping it simple
as much as possible. Therefore, utilization of machine is not preferred much as
it would be raising the price of board.
·
Reduce
type holes: Common drill bit sizes are preferred by the companies while
designing of boards which comprise of 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.2mm, 1.5mm,
2.0mm and 3.0mm. Changing these drill bits are avoided because making changes
by machine takes a lot of time that eventually causes an effect on the cost of
PCB.
·
Limited
track width and track spacing: Likewise, printed company adhere the rule for
the reduction in holes and types holes, similarly they also make it a note to
have minimize track width and spacing. For example, for designing of 0.3mm width,
they make use of 0.5mm and similarly, for spacing they use 0.5mm, when 0.3mm is
required. Eventually, this would help yield a productive printed circuit board
during the fabrication period with an effective cost.
Having discussed all the rules of Printed circuitboard design in this document, you must have got a complete idea of
design rules that are followed by then PCB designing companies.
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