PCB-Specifications

PCB Material:

The abbreviation "FR4" means: F (for flame) and R (forretardancies) and the 4 is a # 4 epoxy.
FR4 features high flexural, impact, superior mechanical strength and bond strength at temperatures up to 130ºC. It is possible to use standard FR-4 with minimum Tg 135ºC for double sided boards which might pass trough 2-3 soldering processes.


Surface finish:

All Printed Circuit Boards(PCB's) have copper finishes on their surface. If they are left unprotected then the copper will oxidise

and deteriorate, there are various protective finishes available,namely:

  •     Hot air solder levelling (HASL)
  •     Organic Solder Preservative (OSP)
  •     Electroless-Nickel Immersion Gold (ENIG)
  •     Immersion Silver ImAg and Immersion Tin  ImSn



Hot air solder levelling (HASL), Lowest cost PCB's, remains solderable through whole manufacturing process, no negative effect at ICT


Electroless-Nickel Immersion Gold (ENIG), Excellent solderability,coplanar - flat surface, excellent shelf life, withstands multiple reflows.Higher cost (approx 5x HASL)

Soldermask

Solder mask or solder resist is a lacquer- like layer of polymer that provides a permanent protective coating for the copper traces of a printed circuit board (PCB) and prevents solder from bridging between conductors, thereby preventing short circuits. Solder mask was created primarily to facilitate wave soldering used in mass assembly. Solder mask is traditionally green but is now available in many colors

Silkscreen

Silk-screening is the process where the manufacturer prints information on the soldermask conducive to facilitate the processes of assembly, verification and repair. Generally the silkscreen is printed for indicating test points as well the position, orientation and reference of the electronic

components that are part of the circuit. Also it can be used for any purpose that the designer may require, for example, the company name, configuration instructions (this was commonly used in old PC motherboards), etc. The silkscreen can be printed on both surfaces of the board. Also the term silkscreen is known  as overlay


Panelization Methods

The main considerations are V-scoring, tab routing or drill and tab routing, you can separate panel with light to moderate pressure after assembly, each method has its advantages and disadvantages:

V-scoring:

One of the main benefits from V-Scoring is that has a better panel utilization compared to the tab routing, as V-scoring don't

need spacing between small units while tab routing requires a certain width of the routing bit.


Routing:


It applied to all kinds of board shape, while V-scoring only works with rectangular shape boards, also the routed board edge is

very smooth except for the connection area, while V-cut will cause the board edge with burr after you breaking the units

away. Include the panel round rail, the idea panel dimension is about 200*300mm(7.9" by 11.8").


Board Thickness

The standard thickness of a PCB is normally around 1.6mm; for a board of this thickness it is not unusual to have a thickness

tolerance of ± 0.15mm. Note when calculating thickness that the supplier of the materials (for inner layer cores) quotes

thickness values that do not include the copper weights. So for a 0.7mm core with double sided 1oz (35μm) copper the actual

thickness will be 0.7mm + 0.035mm + 0.035mm — giving a total thickness of 0.77mm.

 

 

For all PCB manufacturing needs!!!

From step one till delivery and packaging, we look into every detail so you get a high-performance product.Today, we hold the number one spot. As a quality Printed Circuit board manufacturer in China.