With over 10 years productin experience in PCB manufacturing , from Prototyping to finished board with components, also Box build assembly.
C-Alley Co.,Ltd is a leading PCB Assembler , our company in PCBA business and factory located in Shenzhen more than 11 years,
Most of customers are worked with us more than 3 years in PCB FAB, Circuits Assembly, HDI, and PRINTED CIRCUIT DESIGN , some of them are worked with us more than 5 years, we have good reputation in Germany, Japan, Russian,Ukraine and so on.
Equipped with 9 SMT line, each line have AOI, QC, and each projects have engineer checking who will ensure 99.7% workable rate for mass production.
In 2015, China ($8.84 billion) was the dominating supplier of printed circuit assemblies to the US, making up 58% of US imports.
But the challenges are exist in engineering capability and high precision requirements of production devices.
Recently Europe and US (except for some mil spec and medical applications) resulted in development of lead-free (SAC) solders that are tin-based, with additions of silver and copper and with traces of bismuth, indium, zinc or antimony. Initially, the higher soldering liquidus temperature led engineers to specify high glass transition composite substrates (170°-180°C Tg) but careful attention to reflow profiles allowed a return to the less-expensive standard Tg 135°C FR-4 materials. Since the global industry has moved further toward RoHS, many circuit board manufacturing plants have standardized on Pb-free HAL and no longer price that surface at a premium. Indeed, some have scrapped HASL entirely and subcontract that finish, resulting in a cost premium for leaded solder.
Another option, albeit more expensive than Pb-free HAL, is ENIG (electroless nickel/immersion gold). This surface, like OSP, renders the pads very flat and offers the additional advantage of longer shelf life and the ability to wire bond. There is a low but measurable incidence of gold-to-nickel adhesion failure. This is called “black nickel” or “black pad” (see photo, below right) because, not surprisingly, the surface of the nickel turns black. The immersion gold on the pad surface looks normal and solder wets to the gold quite easily. However, with stress or even vibration the components could easily pop off without warning, the result of a brittle fracture at the interface. There are theories about phosphorous levels in the nickel plating solutions being off-spec and causing intermetallics during the gold plating. This problem is rare but does occur.
The most recent advance in surface preparation is ENEPIG, or electroless nickel/electroless.
Here at PCB Train we have developed software tools which assist with pricing up your BOM efficiently and accurately. Read more
What’s a BOM?
A BOM (bill of materials) is the list of materials and parts needed to produce a product. Clients provide us with a BOM so that we can build their product for them. A BOM inquiry lets us present you with a product quote.
Here at PCB Train we have developed software tools which assist with pricing up your BOM efficiently and accurately. If you follow the 3 tips below your BOM will be priced and sourced using the data you have supplied, without manual intervention from us. This improves accuracy, and speeds up processing. We can happily say that 63% of the BOMs we receive already follow these rules. However, we’re looking to increase this percentage, thus reducing the amount of manual processing needed for those BOMs that need some tweaking.
Why they’re green
Have you ever wondered why the majority of PCBs are that iconic dark green colour? The green that you see is actually the colour of the soldermask showing through the glass. In regards to the origins of the use of the green, there are a few theories.
Some speculate that green was the regulation standard when for when PCBs were used by the American military, and the use of it spread from there. It has also been suggested that green could have been the colour of the original solder mask resins, and that we continue to use green as a matter of convention, despite no longer using these materials. In modern circuits a soldermask can actually be made in any colour. However, green has worked well for us so far, and it makes it particularly easy for engineers to see faults in the traces, so many companies tend to stick with it.
Minimum line width is one of the first questions asked of a PCB manufacturer’s capabilities, but the answer rarely includes “depending on copper weight.” To simplify your design process and avoid problems at the time of manufacturing, we will demonstrate how and why line width depends on copper weight. This brief overview gives some near-universal rules for trace width versus copper weight, along with other important considerations when using heavy copper.