2015年7月21日星期二
2015年7月17日星期五
2015年7月8日星期三
All about solder balls for BGA rework
Solder Balls, also called solder spheres, for BGA rework are miniature balls made from different types of solder alloys and are of various sizes. Most common sizes go from 0.20mm to 0.76mm.
List of common sizes used in most consumer electronics bga packages:
Solder balls 0.20mm
Solder balls 0.25mm
Solder balls 0.30mm
Solder balls 0.35mm
Solder balls 0.40mm
Solder balls 0.45mm
Solder balls 0.50mm
Solder balls 0.55mm
Solder balls 0.60mm
Solder balls 0.65mm
Solder balls 0.76mm
Solder balls 0.25mm
Solder balls 0.30mm
Solder balls 0.35mm
Solder balls 0.40mm
Solder balls 0.45mm
Solder balls 0.50mm
Solder balls 0.55mm
Solder balls 0.60mm
Solder balls 0.65mm
Solder balls 0.76mm
They come in Leaded and Lead Free alloys.
One of the most popular brands is PMTC (Profound Material Technology Corp.) from Taiwan.
For the average repair shop they're available in quantities of 25k and 250k containers.
Solder balls are sensitive to moisture and should be kept in a moisture fee environment. They're usually given a 1 year lifetime before their considered unreliable due to environmental exposure.
For the average repair shop, although not encouraged to do so, if the right ball size is not available we can use the next smaller size to perform a job.
When reballing a chip we need to use the corresponding preform (stencil) for the ball size.
We must make sure we close the solder balls container soon after we've finished using it to diminish moisture exposure.
Solderballs can be cleaned if they have become dirty by flux or any other foreign material. We just dump them in a bowl of alcohol or similar chemical and wash them off then let dry.
We must be aware that it is common to find some smaller (sometimes significantly smaller) solder balls within a given solder ball container. If during reballing a chip we see this we must remove this smaller ball and re-place with the right size. If we dont catch this while reballing and we solder the balls onto the chip, the chip will not have good contact, in comparison to the others, on that pad and will soon cause a cold solder joint.
2015年7月2日星期四
How BGA Rework Station Use to Rework the PCB
BGA rework station is the best reworking station for the printed circuit board (PCB) of the microprocessor of laptops, PCs, XBOX, and play station. Reworking is a word use for the resurfacing operation or repair of a printed circuit board (PCB) assembly, generally including desoldering of surface mounted electronic parts. Mass preparing procedures are not related to single device repair or replacement, and specific manual methods by master work force utilizing proper equipment are required to replace defective parts. Ball grid array (BGA) apparatuses especially require skill and suitable devices. A hot air gun or hot air station is required to hotness mechanisms and melt solders, and particular devices are utilized to get and position frequently small segments. A BGA Rework Station is a spot to do this work, the instruments and supplies for this work, regularly on a workbench. There is a certain reason for reworking of printed circuit board (PCB) and these reasons are the poor solder joints due to the reason of faulty components, and assembly or thermal cycling. Unnecessary drops of solder that connect all joints that should be isolated from each other. Engineering parts changes and upgrades etc.
The rework may include numerous segments, which must be chipped away at one by one without harm to encompassing parts or the PCB itself. All parts not being chipped away at are ensured from hotness and harm. Thermal stress on the electronic assembly is kept as low as would be prudent to anticipate unnecessary constrictions of the printed circuit board which may cause quick or future damage. Most soldering is carried out with lead-free solder, both on produced assemblies and in rework, to avoid the health and natural risks of lead. Where this precaution is not essential, tin lead solder dissolves at an easier temperature and is simpler to work with apportioned solder paste on the cushions of a QFPs. Cover and circles for reballing also by heating the single surface mount device with a hot air gun to melt all of the soldering joints in it and the printed circuit board mostly worked in starts followed by the removing of the surface mount device. The pad array on the conductor board should then be cleaned of previous solder and it is easier to remove these residues by heating them on a soldering iron or hot air gun can be used with desoldering braid. The exact situation of the new unit onto the ready cushion exhibit requires skilful utilization of an exceptionally correct vision arrangement system with high determination and amplification. The littler the pitch and size of the parts, the more exact working must be conducted. At the end new surface mount device is placed on the board. Dependable solder joints are encouraged by utilization of a solder profile which preheats the board, warms all the associations between the unit and the PCB to the liquefying temperature of the weld utilized, and then legitimately cools them.
This is how a BGA rework station do all these reworking and the reason to use BGA rework station is it prevent the printed circuit board from being overheating and which cause less damage in the reworking process.
The rework may include numerous segments, which must be chipped away at one by one without harm to encompassing parts or the PCB itself. All parts not being chipped away at are ensured from hotness and harm. Thermal stress on the electronic assembly is kept as low as would be prudent to anticipate unnecessary constrictions of the printed circuit board which may cause quick or future damage. Most soldering is carried out with lead-free solder, both on produced assemblies and in rework, to avoid the health and natural risks of lead. Where this precaution is not essential, tin lead solder dissolves at an easier temperature and is simpler to work with apportioned solder paste on the cushions of a QFPs. Cover and circles for reballing also by heating the single surface mount device with a hot air gun to melt all of the soldering joints in it and the printed circuit board mostly worked in starts followed by the removing of the surface mount device. The pad array on the conductor board should then be cleaned of previous solder and it is easier to remove these residues by heating them on a soldering iron or hot air gun can be used with desoldering braid. The exact situation of the new unit onto the ready cushion exhibit requires skilful utilization of an exceptionally correct vision arrangement system with high determination and amplification. The littler the pitch and size of the parts, the more exact working must be conducted. At the end new surface mount device is placed on the board. Dependable solder joints are encouraged by utilization of a solder profile which preheats the board, warms all the associations between the unit and the PCB to the liquefying temperature of the weld utilized, and then legitimately cools them.
This is how a BGA rework station do all these reworking and the reason to use BGA rework station is it prevent the printed circuit board from being overheating and which cause less damage in the reworking process.
High Automatic Rework System
Detailed Features
1 Large area of infrared carbon fiber Pre-heating system, with the advantage of pre-heating fast and evenly and no light pollution.
2 Temperature parameters protected by limits of authority, for avoiding error settings.Repair
3 Ten segments of temperature control process, suitable for all kinds of BGA Rework Station.
4 Unlimited storage of the temperature profile, just need press one key to use the profile.R
5 Three K-type sensors available can realize the high precise temperature testing of each point of PCB or BGA, and PC can generate report of curves analysis automatically.
6 Desoldering and soldering automatically, No need the manual adjustment
7 BGA rework station ZM-R6000 Hot air flow can be adjustable to meet the demand of any chips
8 USB Connection driver-free, PC control
9 The bottom hot air lifting control available in the front panel, bga machine is convenient to adjust at any time.
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