With the rapid development of mobile phone, electronic, telecommunications and other industries, Printed Circuit Board industry continues to grow rapidly, at the same time also prompted people to require more and more about the PCB number, weight, color, material, precision, reliability and so on.
But because the competition of the PCB market, PCB material is also in the rising trend.So more and more manufacturers in order to enhance the core competitiveness, often use low price to monopolize the market. However, behind these ultra low cost is , reduce the material cost and production cost, which makes PCB easy to crack, easy to scratch, the precision and other comprehensive factors of non-compliance, will seriously affect the product solderability and reliability, etc.
For many electronic engineers and purchasing personnel are not sure, in fact, there is no standard method of judgment, but you can from the following points to have a initial judgement:
The first method is to distinguish from the appearance, the other is from the PCB board itself to judge its quality specification requirements.
Firstly, distinguish the quality of the circuit board from its appearance:
First to distinguish the material used for the plate, and then from the board's ink color, copper deposition, surface treatment, smell up.
The material usually are as followings:
The ordinary HB board, 22F is the cheapest and easy to deform and break, only can be used as single panel; component surface color is dark yellow with irritating odor, rough copper,and thin.
Single sided 94V0 and CEM-1 boards, the cost is higher than the cardboard, but cheaper than the semi-glass fiber board, the component surface is light yellow, mainly for industrial boards and power panels which have requirements of fire rating.
FR4 glass-fiber board, high cost but good strength, basically most of the double-sided and multilayer boards used this material, copper can be very precise, relatively the unit board is also heavier.
Surface treatment include: OSP circuit board, Immersion Gold circuit board, Hot Air Solder Leveling circuit board and other processes, all require PAD surface can not be contaminated, otherwise it will affect solderability.
Also the Standard of size and thickness, the welds appearance also should be considered because it may influence the quality of soldering.
Secondly,Super quality PCB boards need to meet the following requirements:
1. To meet the requirements of electrical connections;
2. The width, thickness and distance of the line should meet the requirements to avoid hot, broken or short circuited.
3. Copper surface should not easy to oxidize, or it will affect the installation speed and can not be used for long after oxidation.
4. There is no additional electromagnetic radiation.
5. Shape without deformation. Now all of them are mechanically installed, and the hole position of the circuit board and the deformation error of the line of design should be within the allowable range.
6. High temperature, high humidity and resistent to special environment should also be considered.
7. The mechanical properties of the surface shall comply with the installation requirements.
The above are some basic methods to judge the quality of PCB boards during the purchase of PCB boards, be sure to polish your eyes to choose a right PCB Manufacturer.