PCB Blogger-China PCB Factory,HOYOGO

       PCB warpage refers to the problem that the substrate appears as a  plane  unevenness during the PCB manufacturing process.  This problem can lead to poor electrical connections, damaged components, signal interference, and more.   Therefore, enough attention should be paid to the problem of PCB boards warpage. So what is the PCB warpage standard? What causes PCB warpage?       I.  PCB Warpage Standard The PCB industry attaches great importance to the problem of PCB warpage, so it also stipulates some warpage standards and clarifies the specific numerical requirements for warpage. The current standard for PCB warpage is mainly the IPC-6012 specification.     The IPC-6012 specification is a general specification adopted by the PCB industry, which mainly stipulates the following standards: 1) Single   sided or double   sided  board s cannot exceed 0.75% of the size; 2) Multi-layer boards cannot exceed 0.50% of the size.     II . Causes of PCB Warpage The appearance of PCB warpage i

      Blind & buried PCB is a high density, high precision printed circuit board. Its special structure and complex technology are widely used in high-end electronic products. If you buy poor quality products, there will be various problems need to be dealt with. So in order to avoid this situation, how should we judge the quality of blind & buried vias in PCB?       1.  Check the diameter, depth and wall thickness of blind vias These aspects of qualified blind  &  buried vias all meet the standard requirements, while unqualified  one s may have quality problems in these aspects .  Such as the hole diameter is too large, the hole depth is not enough, the hole wall is too thin and so on.       2.  Check the piercing quality of blind vias Qualified blind & buried vias should have no burr, no broken edges, and no crack when piercing, while unqualified ones may have these quality problems. These problems may lead to failure of buried blind s in use.     3. Check the plating

      According to JPCA-ES-01-2003 standard: Copper clad laminates with chlorine (C1) and bromine (Br) contents less than 0.09% Wt (weight ratio) respectively (at the same time, the total amount of CI+Br  ≤  0.15% [1500PPM]) are defined as halogen-free copper clad laminates.  So what are the characteristics of halogen-free PCB?   1.   Environmental  P rotection Halogen-free PCB  board realizes environmental protection and non-toxicity of PCB by replacing or replacing harmful elements.     2.  F lame  R etardant Most of the halogen-free materials are mainly phosphorus -based   and phosphorus - nitrogen -based .   The polymer resin containing phosphorus and nitrogen compounds will form a carbonized film when it is burned, which can isolate the burning surface of the resin from contact with the air, so that the fire can be extinguished and the flame retardant effect can be achieved.     3.   G ood  I nsulation Halogen-free PCB uses phosphorus or nitrogen instead of halogen atoms, which re

       During the reflow soldering  technology , PCB  will  encounter soldering defects for various reasons. So what is the cause of the defect?  How to solve these defect?       1.  Tombstone Phenomenon In reflow soldering, chip components often stand up, which is called tombstone. This is a defect that often occurs in reflow soldering technology.   Cause:   The wetting force on the both sides of the component is unbalanced, so the moment on both ends of the component is also unbalanced, resulting in the occurrence of tombstoning.   The following situation will cause the wetting force on the both sides of the component is unbalanced: 1)  Pad design and layout are unreasonable. 2) Solder paste and solder paste printing is uneven. 3)  Patch displacement. 4)  The furnace temperature curve is not set correctly.   Solution: 1) Improve pad design and layout. 2) Choose a solder paste with higher activity to improve the printing parameters of the solder paste, especially the window size of th

      If the PCB adopts reflow soldering  process , then the solder needs to be applied to the soldering part before soldering.   The main methods of applying solder to solder parts are the solder paste method, the pre-solder method, and the pre-formed solder method.       1. Solder  P aste  M ethod Applying solder paste evenly to the PCB pad pattern is the most commonly used method in the reflow soldering  process. The purpose is to ensure that the pads corresponding to the SMT components and the PCB achieve good electrical connection during reflow soldering, and have sufficient mechanical strength. There are two methods to apply solder paste: Injection  drop  coating method and printing coating method.  The injection drop coating method is mainly used in the development of new products or the production of small batches of products, and can be operated manually.  Although the speed is slow and the precision is low, it has high flexibility and saves the cost of manufacturing templates

       In the PCBA processing process, many  technologie s will cause a certain degree of pollution to the PCBA.   The presence of these pollutants will not only affect the appearance of the PCBA, but also negatively affect the performance of the PCBA. Therefore, it is very important to clean the PCBA.       PCBA pollutants mainly include polar pollutants, non-polar pollutants and particle pollutants.     Polar pollutants are mainly oxides of electronic components or PCB, active agent residues in flux, sweat or fingerprints of operators, and solder residues.   Such pollutants will cause the component pins to be corroded, and will also cause the PCBA circuit to fail, and will also cause delamination of the PCBA and the conformal coating.     Non-polar pollutants are mainly rosin residues in flux, adhesive residues, operator fingerprint grease, and anti-oxidation oil residues. Such pollutants will affect the conductivity and reliability of PCBA, and will also reduce the effect of conform

       With the development of electronic processing technology and electronic technology, the overall demand for PCB is increasing. Many PCB manufacturers only provided PCBA processing methods in the past, and now many manufacturers provide   PCBA one-stop service . So what are the advantages of PCBA one-stop service?   1. Customers choose PCBA one-stop service, which has great advantages in reducing the cost of purchasing materials. Because  PCBA manufacturers  can receive orders from all over the world,  the customer demand is relatively large,   so  the corresponding components are purchased in large quantities. They also have stable component suppliers who have cooperated for many years, so they can get the lowest purchase price.     2. It can reduce labor costs. If you buy materials yourself, you must have your own purchasers, including PCB purchasers and component purchasers. These are not small expenses.     3. It can reduce the company's  warehousing expenses . The storage