Hello Engineers,
I'm Prosanta Biswas From Kolkata, West Bengal, India, and i'm an Electronics Hardware Design Engineer.
if you have any query feel free to contact me:
Email: prosantalok085@gmail.com
WhatsApp: +91 6291579068
What is BGA (Ball Grid Array) and Why BGA is Needed?
BGA or Ball Grid Array is one type of packaging for Surface Mount Technology (where SMD electronic components are actually mounted or affixed on the surface of the SMT printed circuit board). A BGA package has no leads or pins. The Ball Grid Array gets its name because it is basically an array of metal alloy balls arranged in a grid. These BGA Balls are normally Tin/Lead (Sn/Pb 63/37) or Tin/Silver/Copper (Lead-Free).
Advantages of BGA over SMD
The PCB or Printed Circuit Board in today’s electronic devices and gadgets are densely populated with electronic components. The size of the Circuit Board will increase with increase in number of electronic components. In order to squeeze the size of the PCB, SMDs and BGA Packages are used because both SMD and BGA are smaller and slimmer in size and occupy very little space on the PCB.
BGA components provide better solution for many Types of PCB, but care is required when soldering BGA components to ensure that the BGA solder process is correct and is reliable.
BGA offers following advantages over SMD Components:
Improved PCB design as a result of lower track density.
The BGA package is robust.
Lower thermal resistance.
Improved high speed performance and connectivity.
BGA Soldering Process
During the initial stages, BGA technology was a matter of concern. People had doubts on solderability and reliability of BGA components. In BGA, the pads are under the device and not visible and hence it is necessary to ensure the correct process of soldering and inspection.
Today, BGA soldering techniques is tried and tested and has been proved and trusted to be very reliable. It has also been learnt that once the process is set up correctly, BGA solder reliability is mush higher than that for quad flat packs (QFP) or any other SMD Package.
BGA Rework / Repairing - Hand Soldering and Desoldering of BGA
Rework and hand soldering of BGA Packages is the toughest part. It needs practice to do the job. Let us understand Desoldering and soldering of BGA packages by hand
BGA Desoldering by Hand
The most common practice to desolder BGA is hot air. Here are the steps to desolder BGA Package using Hot Air:
Apply liquid flux on the sides of the package.
Preheat the package from both top and bottom. Heat can be given from the bottom using a preheater while heat from the top can be given using a Hot Air Rework System. Goot Hot Air SMD / BGA Rework System can be used here.
Now using the correct BGA Nozzle, give heat on top of the BGA Package.
The solder balls underneath the BGA package will melt. Pick up the package with a Tweezers OR using vacuum pick-up tool.
BGA Soldering by Hand
Again the most common practice to solder BGA is hot air. Here are the steps to solder BGA Package using Hot Air:
Once the BGA Package is removed, clean the pad and remove any excess solder from the board.
1.Apply Flux Paste (Not Liquid Flux) on to the pad. Paste flux will help solder balls to stick so that they do not fall or change position.
2.Place solder balls very carefully on the pad.
3.Apply paste flux to the bottom (soldering side) of the BGA package.
4.Carefully place the BGA Package on the solder balls.
5.Preheat and then apply Hot Air with Hot Air Blower from both top and bottom.
6.Solder balls will melt and get soldered.