![]() ![]() Every electrical device, from mobile phones to PCs, contains at least one PCB. The Printed Circuit Board is the most vital component in an electrical circuit. And they also helped to reduce the price of the product. PCBs worked to minimize the size of an electrical device. Without the innovation of the printed circuit board, most of the tech and electrical items we utilize today would not be conceivable (PCB). Once the part has been soldered to the PCB you can be confident that moisture sensitivity is no longer a concern.PCB baking is one of the hot topics when discussing PCB. It is very unlikely that during normal production operation any IC will undergo the sort of rapid heating experienced during reflow soldering. Once ICs have been successfully baked, APS immediately dry packs them with desiccant and a moisture level indicator card to ensure successful problem-free soldering. Parts can be baked at low temperature (40 degrees Celsius) in an ultra-low humidity environment for a long period of time (usually 9 to 30 days dependent upon part type and thickness.) Alternatively, they can be baked at 125 degrees Celsius for a much shorter time (usually between 5 and 48 hours.) Each of these methods ensures that any moisture within the chip evaporates in a controlled manner – no chip damage occurs during the baking process. There are various methods of baking – which method to use is dependent upon the nature of the part and the required timeline of the job. ![]() This ensures that when the parts are soldered there is almost zero moisture in the packages and the risk of part damage (or “popcorning”) is eliminated. MSL 6 parts can only be left out for 6 hours before baking is required.īaking integrated circuits allows the water to evaporate gradually and completely. These levels range from MSL 1 (which can be left in the open indefinitely and will not absorb any moisture) to MSL 6. The higher the Moisture Sensitivity Level, the more rapidly the part will absorb water. Moisture sensitivity of a particular integrated circuit is defined by its Moisture Sensitivity Level. The visible damage done to the part is called “popcorning.” ![]() The force of these bubbles (the force of the expanding water) deforms the part and often damages the internal components. The boiling causes bubbles to form inside of the plastic packaging. Due to the high temperature of the reflow process, the water absorbed by the part boils. The major concern with moisture sensitive parts is that the plastic packaging around the part will absorb water (typically from the air.) When it comes time to assemble a circuit board and the part undergoes reflow soldering, the moisture in the packaging can have very destructive effects. ![]()
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