PCB Blogger-China PCB Factory,HOYOGO

The ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold) technology, is the addition of a layer of palladium between nickel and gold. In the deposition reaction of gold replacement, the electroless palladium layer protects the nickel layer from excessive corrosion by the replacement gold and is well prepared for immersion gold process. ENEPIG process : Degreasing ---- Microetch ---- Pickling ---- Pre-dip -----Activating Palladium ---- Chemical Nickel (Reduction) ---- Chemical Palladium (Reduction) ---- Chemical Gold (Replacement) ENEPIG technology is applied to the surface treatment of package substrates. In the ENEPIG process, by controlling the palladium on the nickel layer and controlling the ENIG, accurate deposition thickness and uniformity of the gold layer are obtained to achieve a good contact surface. Through the comparison of wire bonding ability, solderability and aging resistance between ENEPIG pad and electroplated nickel gold pad, it is verified that E

At present, there are three main types of PCB potting adhesive , namely polyurethane potting adhesive, epoxy resin potting adhesive, and silicone potting adhesive. Each has its own advantages and disadvantages, so how do we choose the potting adhesive in the process of preparing the PCB? (1)Polyurethane Potting Adhesive The temperature requirement does not exceed 100 degrees Celsius. After the potting, there will be many bobbles. The potting conditions are under vacuum and the adhesion is between epoxy and silicone. Advantages : Good low-temperature performance, shockproof performance is the best of the three. Disadvantages : Poor high temperature resistance. After curing, the surface of the colloid is not smooth and the toughness is poor. The aging resistance and UV resistance are weak, and the colloid is easily discolored. It is suitable for potting low electrical heating indoor electrical components. (2)Epoxy Resin Potting Adhesive Advantages : It has excelle

The PCB solder mask is a heat resistant coating material that can be applied to selected areas to prevent solder from depositing during subsequent soldering. The solder mask material can be liquid or dry film; it is also very effective in preventing surface damage of the PCB during PCB assembly operations. If the test point, ground pad or even the component pins are accidentally stained with a solder mask, these are commonplace. However, it does not mean that these PCBs are definitely scrapped. There are several safe and reliable methods for removing the solder mask on the PCB surface: scraping, milling, micro-grinding and chemical stripping; each method has its own advantages and disadvantages. Scraping This method is not peculiar and has large noise. A skilled technician typically removes the solder mask from unwanted areas with a knife, scraper or chisel. This technology is easy to control and requires no special settings. However, if the removal area is l

The aluminum PCB is a kind of metal-based copper-clad laminate with good heat dissipation function. Generally, a single-sided aluminum PCB is composed of a three layers structure, which is a circuit layer, an insulating layer, and a metal base layer. Aluminum PCB is commonly used in LED lighting products: It has a front side and back side, the white side is weldable LED pin. And the other side presents aluminum color, which is usually coated with a thermal grease and then in contact with the thermally conductive portion. Glass fiber board alias: Fiberglass board (FR-4). This is a common material for rigid PCBs. It is made of fiberglass material and high heat resistance composite material and contains no harmful asbestos ingredients. It has high mechanical properties and dielectric properties, good heat resistance and moisture resistance, and processability. It also has the characteristics of sound absorption, sound insulation, heat insulation, environmental protection and flame reta

Copper clad is an important part of PCB design. The so-called copper clad is to use the unused space on the PCB as the reference surface, and then fill it with solid copper. These copper areas are also called copper pour. The significance lies in: reducing the ground wire impedance, improving the anti-interference ability; reducing the pressure and improving the power supply efficiency; connecting with the ground wire can also reduce the loop area. At the same time, it also makes the PCB not be deformed as much as possible. At high frequencies, the distributed capacitance of the layout on the PCB will work. When the length is greater than 1/20 of the corresponding wavelength of the noise frequency, an antenna effect will occur and the noise will be emitted through the wiring.If the copper cladding in the PCB is poorly grounded, the copper cladding becomes a tool for propagating noise.Therefore, the copper cladding must be properly treated. There are two ways to fill the PCB wi