Specifications

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you give yourself enough workspace to add more electronic components if
necessary.
4) After that the PCB designer must select the number of layers that he
wants for his design. The designer can choose from 2 layers, 4 layers, or
6 layers. 2 layers are mostly used for simple designs, 4 layers is
preferably applied for medium-density designs, and 6 layers mainly works
for high density or complex designs.
5) If the user/designer determines that he would like to select either 4 layers
or 6 layer PCB board then they have option for adding additional plane
layers. Plane layers are sheets of copper material.
6) Subsequently the board has additional features such as coating for the
PCB. The designer can decide whether he would want a soldermask or a
silkscreen. Our best bet when designing our PCB is to use soldermask,
which is a green coating on the circuit board.
7) Then we have an option of choosing which thickness you would like to
use. On the PCB123 software, you can select either 0.031 inches or 0.062
inches. For our design which should use 0.062 inches as it is most
recommended.
8) Last of all, the copper weight is the next factor in the development of the
printed circuit board. There are two alternatives to select from for the type
of copper weight that you want: the 1 – oz or the 2.5 oz. The HVAC control
system will want a 1-oz to make the finished product for our PCB.
The common standard that is referred to for the design of PCB‟s is IPC-2221A.
IPC stands for the Institute for Interconnecting and Packaging Electronic Circuits
which is the authoritative figure that controls every aspect of PCB design,
manufacturing, and testing. The key document that describes PCB design is IPC
- 2221 which is specifically titled “Generic Standard on Printed Board Design.”
When fabricating the PCB, the rules that must be considered when making the
foundation for every component being surface mounted on entails board size
(tracks), trace width and spacing, pad sizes, holes sizes, and hole spacing.
You may ask yourself, what are the factors that involve picking an accurate board
size (track) for your PCB? These parameters depend upon the electrical
requirements of the HVAC design, the routing clearance and space available,
and your own preference. Standard board spacing for routing is 0.3 inches with
an additional 1 to 2 inch border on the board for processing. Larger track width is
preferred more because they have low direct current resistance and relatively
small inductance. Lower limit of the track width will depend upon the track
resolution that the manufacturer for the printed circuit board is capable of
producing. Also the size of the board will have a particular amount of resistance
given off. Finally, the thickness of the copper substrate will have a huge effect on
the printed circuit board when soldered upon.