YOU WILL NO LONGER BE CHEATED BY COST
Why people pay different prices for identical PCB with the same materials and technical requirements? What is it that determines the price of PCB? What should you pat attention to when you make an estate of the price? Here we will tell you the details few people will reveal.
Now make a guess about what takes up the majority of PCB pricing. I believe that most people’s answers will definitely be the material, since few people have a full understanding of the whole process of PCB manufacturing. The right answer, however, would be the manufacturing costs.
|Manufacturing Costs||DFM||material utilization
|minimum width or spacing|
|Minimum Hole Size|
|the rate of the
copper thickness/minimum size hole
|area of copper|
and characteristic impedance
|PTH and hole-plugging|
|dry and wet films of layers|
|Process Capability||hardware and software|
|one-time pass rate
or scrap rate
|broken pieces on one set|
There are three factors that determine the manufacturing cost.
Firstly, it is DFM(Design for Manufacturing). PCB suppliers will decide on how many panels should be cut from the original laminate. That is to say, the shape and size of your PCB can affect the material utilization rate and thus affect the manufacturing costs. And if the rate rises by 10%, the suppliers will save USD0.5. The more holes there are, the higher the cost of drilling and managing holes (PTH) will be. The drilling cost have something to do with the hole size, board thickness, copper thickness and the number of layers. The cost of PCB with smaller hole size, thicker board, thicker copper and more layers will rise by 15% or so. The cost of slot holes and non-circular holes would be 2.25 times as much as the times of drilling in real terms. If the minimum width or spacing is equal or less than 4mils, the cost will rise. The smaller the BGA pad is, the higher the cost would be. If the minimum hole size is less than 0.3mm, the cost will rise. The cost will be higher if the rate of the copper thickness/minimum size hole is more than 8. The area of copper will make the cost of materials, water and electricity higher. The difficulty of differential impedance and characteristic impedance will increase the cost by 7.5-15%. And other difficult technical requirements will increase the cost as well. As for surface finish, HASL and OSP are the cheaper ones. The average cost of PTH hole-plugging is about USD3.3 per square meter. And the cost of a piece of dry film is about USD3.3 more than a wet one. When it come to forming, the CNC technique of single-sided PCB of small volume will 1.5 times more than punching for large volume. Double-sided punching will cost USD4.3 per square meter more than CNC. And some molds with high requirements for precision cost about 3 times as much as the usual ones.
Secondly, it is the process capability. The cost will be different if the investment in hardware and software is different. PCB manufacturers contrapose solder masks manually or with CNC(Computer Numerical Control) contraposition machines. The price of a set of contraposition machine is about USD 650 thousand. The depreciation will increase the cost and if it is higher than the cost, many manufacturers will choose outsourcing.
Thirdly, it is one-time pass rate or scrap rate. Customers generally demand that the percentage of broken pieces on one set should be less than 1.5-3%. Thus if the scrap rate is more than the percentage, it is obvious that the cost will rise. If the quality cannot satisfy customers’ demands, the one-time pass rate will be low. And the quality is closely linked to the supplier’s productivity and quality control.
Direct Materials Costs
Direct Materials Costs
|potion||brand and level|
|Copper Spheres,Tin Bars and OSP||brand and thickness|
|Matching Tools||forming mold|
|films, character stencils, solder mask stencils and drills|
The cost of direct materials takes second place in the PCB pricing.
There are five factors that determine the cost of direct materials.
Firstly, it is the laminated materials. There may be a huge difference in pricing laminated material between different factories. The materials can, for example, be FR-4, FR-1 or CEM-1. And FR-4 will cost 3.6 times more than FR-1 or CEM-1. FR-1 can be divided into 94V0, 22F. These two kinds of materials and CEM-1 are mainly used for single-sided PCB. And their pricing differences range from USD 3.3 to USD 11.0. The board thickness can be, for example, be 0.8mm, 1.0 mm, 1.2mm or 1.6mm. For each sheet of laminated material, the later one will cost about USD 2.2-4.3 more than the former one. Generally speaking, the copper thickness of the inner layers will be 35um and that of the outer ones will be 17.5um. Each sheet of laminated material with high TG will cost USD 2.2-5.5 more than that with middle TG. And the cost of that with high TG will be USD 2.2-5.5 higher than that with low TG.
Secondly, it is the ink. The cost of ink has something to do with brands, colors and varieties. Prices of ink provided by different will be greatly different. Green ink is mostly used in solder mask and plugging holes. If black or blue ink is used to plug holes, the cost will rise by 7.5% or so because the scrap rate will rise. As for the liquid photosensitive ink, prices are similar. The dry film will cost 1.5 times as much as a dry one. Potion pricing is determined by its level and brand. Copper spheres,tin bars and OSP will also determine the cost of direct materials. The thickness customers need should be take into consideration. The cost of these materials is also related to brands. The thicker the gold thickness of the gold finger cardboard is, the higher the cost will be. Among the four kinds of surface finish(immersion golf, Lead-Free HASL, HASL and OSP), the cost of immersion gold is the highest and Lead-Free HASL take the second place. The cost of HASL and OSP is the lowest. Another material cost comes from manufacturing matching tools. The molds can be divided into punching molds and external molds and the cost ranges from USD 435 to USD 1740. When manufacturers get ENC(Engineering Change Notice) each time, the former molds cannot be used any longer. As for normal double-sided or multi-sided PCB, some slot holes will be made by punching molds. The cost of text fixture will be about USD 175-217,5 according to varying levels of difficulty and especially the number of test points. Films, character stencils, solder mask stencils and drills are all factors that determine the cost of manufacturing matching tools.
|Period Costs||administrative expenses||maintain product
manufacturing and management
|selling expenses||generate customers and serve|
|financial expenses||house rent, the cost
of water and electricity
|Other Costs||schedule||e.g. quick-turn PCB|
Labor costs in different regions may be greatly different, but the average wage of workers is about USD760 a month.
Period costs include administrative expenses, selling expenses and financial expenses. The administrative expenses are used to maintain product manufacturing and management. The selling expenses are used to generate customers and serve. And the financial expenses includes house rent, the cost of water and electricity and freight.
The extra cost can also arise from the schedule when customers need quick-turn PCB. Besides, customers may also pay extra for speedy services.