Getting to know the board size
A panel is one of the most important raw which is needed to produce a PCB. Size of the board is another huge price determining factors, as the bigger the board is, the more material will be required to build it. This point might sound straight forward but it’s not exactly as simple as that because, depending on the specified dimensions it is very much possible to have a board that takes up less area estate but is actually higher in cost.
This happens because the overall size of the panel used to manufacture the board; sometimes one dimension fits the panel a lot better than the other does. Let’s consider two parts with the same total square inches per board. Board A is 2sq.in x 6sq.in and board B is 3sq.in x 4sq.in. A panel of standard production will produce more of the 3sq.in x 4sq.in variety of boards then the 2sq.in x 6sq.in variety of board. Thus, the cost for each board would be reduced for the 3sq.in x 4sq.in boards.
Pay attention to surface finish
A minor factor to consider regarding PCB production involves the costs associated with a given finish. Some finishes boast higher grades and offer longer shelf life, thus adding to the overall cost of production. One of the more common and low-cost surface treatments is HASL, which offers good solderability but is rated unfavorably on other counts. ENIG, by comparison, scores favorably in most categories yet only commands a slight price difference.
Each of the surface treatment options offers unique features:
- HASL: Solderability
- LFHASL: Solderability
- OSP: Solderability
- IMM Ag: Solderability, Al wire bondable
- IMM Sn: Solderability
- ENIG: Solderability, Al wire bondable, contact surface
- ENEPIG: Solderability, Al wire bondable, contact surface
- Elec Au: Solderability, Al/Au wire bondable, contact surface
Pay attention to thickness of the PCB and aspect Ratio
Until recently, the thickness of a PCB had played only a minor role in the overall cost, though all that is liable to change in the coming years. Thicker material can be costlier to procure, laminate and form into a printed circuit board, especially if the design itself is highly intricate.
Thinner material will generally put a line of PCBs into a slightly lower cost bracket because less material is required for the production at hand. The costs of a board in regards to thickness can also be impacted by the type of material used in a given production.
The standard thickness for a PCB is 1.6mm (0.063″). In recent times, thicker boards have become more expensive, though an industry-wide going rate has never been established. Overall, it depends on the manufacturer whether a thinner board of 0.8 mm will cost less or equal to a board of standard thickness.