The main reasons affecting the success of BGA repair can be divided into three categories: precision of mounting, precise temperature control, prevention of PCB deformation, and of course other influences. However, these three factors are difficult to grasp, so they are listed to solve together. The following is the main reasons affecting the success rate of BGA repair.
First, the welding of bga components need to ensure a certain pasting precision, otherwise it will cause air welding, tin ball in welding heating, there is a certain self-centering effect, allowing a slight deviation, during the pasting, the center of the shell and the center of the screen frame approximate coincidence, can be regarded as the correct pasting position. In the case of not using optical bga repair table, you can also judge whether the contact is based on the feel when moving the bga (this is subjective, everyone's feeling may not be the same). Optical grade BGA repair table can directly see whether the bga components and pad alignment, and automatic welding. At present, the bga repair table in China basically adopts the hot air up and down and infrared preheating at the bottom, so it is necessary to use a reasonably designed air nozzle to prevent the hot air from moving the bga when heating.
Two, reasonable, high quality repair needs to adapt to its repair temperature curve, grasp the temperature and time, to be in the range of bga can bear, under standard circumstances, lead less than 260℃, lead less than 280℃. If the temperature control is not accurate enough, the temperature fluctuation range is large, then it is easy to damage the bga components. At the same time, the heating time should not be too long, and the number of repair should not be too much. It will cause the oxidation of bga at high temperature, and the life of bga will be shortened for a long time.
Three, when welding or disassembling bga components, because only the corresponding BGA components are heated separately, it is easy to cause the temperature difference between bga and the surrounding area is too large, and the board is easy to deformation and damage. Therefore, when repairing bga, it is necessary to fix the board and the location of bga. Generally, the lower air nozzle will be used to resist the PCB board when repairing bga repair table. And the lower part of the wind can play a certain supporting role, if the use of air gun welding, then it is necessary to fix the board, to prevent the deformation of heating directly lead to PCB damage, at the same time, also need to preheat the PCB board as a whole, in order to reduce the temperature difference for the purpose of effectively prevent deformation.
BE MY FRIEND:
Check out my email address: dtf2009@dataifeng.cn
warning! are you avoiding Professional BGA Repair Station Manufacturer mistakes?
#dataifeng #BGA rework station #manufacturer #factory #factorywork