PIH/PIP parts should also be placed on the second side of the furnace, unless the length of the solder fillet does not exceed the thickness of the board, otherwise the foot that protrudes from the surface of the PCB will interfere with the steel sheet on the second side, which will make the second side The solder paste printed steel plate cannot be flat on the PCB, which causes the solder paste to print abnormally.ģ, Some components may have soldering work inside. If there are small and small BGA parts, it can also be placed on the first side of the reflow oven, as long as it can effectively avoid PCB deformation.Ģ, parts can not withstand too much high temperature parts should be placed on the second side of the reflow oven, this is to avoid parts too much temperature and damage. LGA and BGA parts should be placed on the second side of the furnace as much as possible, so as to avoid the unnecessary risk of re-soldering during the second pass to reduce the chance of empty/false welding. Which SMD parts should be placed on the second side of the reflow oven?ġ, Large components or heavier components should be placed on the second side to prevent the parts from falling back into the furnace. Some boards may require a re-return to the furnace because of the maintenance relationship. The general resistance and capacitance are usually required to be reflowed at least three times, in order to meet the requirements.
Again, the parts on the first panel must pass through the reflow oven twice, so the temperature resistance must be able to withstand the temperature of two reflows. For more information on designing PCBs, please visit ANDWIN CIRCUITS CO.,LTD. Because the first surface part will be placed directly on the bottom surface of the circuit board when facing the second side, when the board enters the high temperature of the reflow area, it will not fall off the board because of excessive weight. Second, the smaller parts do not risk falling when the second reflow oven is over. So, what should you think about when manufacturing double-sided reflow? Which SMD parts should be placed on the first side of the reflow oven?įirst of all, the smaller parts are recommended to be placed on the first side of the reflow oven, because the deformation of the PCB will be smaller when the first side passes through the reflow oven, and the precision of the solder paste printing will be higher, so it is better placed Smaller parts. For example, when the board goes to the second reflow furnace, the parts on the first side will fall due to gravity, especially The board flows to the furnace where the reflow zone is hot. Because of the limitations of the process, some problems may occur. Single-sided reflow is used less because double-sided reflow saves board space.ĭouble-sided reflow requires two reflows. Introduction to PCB double-sided reflow process (SMT)Ĭircuit board assembly technology, now popular in the industry is full-board reflow soldering (Reflow), this technology can be divided into single-panel reflow and double-panel reflow.
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