There are thousands, if not hundreds of thousands of technological advancements and innovations that make the things we take for granted every day possible. From the microchip to flexible circuits, there are tiny things inside the things inside your pocket, your briefcase, and your backpack that you don’t even realize are there, and they have all undeniably changed your life. Ball grid arrays are one of those things.

A ball grid array, or BGA is a direct descendent of the pin grid array (PGA) and used to conduct electrical signals from the integrated circuit to the printed circuit board of an electronic component. Virtually all electronics contain printed circuit boards. While a PGA is comprised of pins, the BGA is made up of ball of solder – stuck to what is known to the "package".

While pin grid arrays were effective, they did present a few disadvantages. For example, if you were to empty the contents of your pockets, chances are you would be left with your keys, some change, maybe some lint, and your cell phone. Years ago, cellular phones were the large artifacts you’ll now only see in a re-run of Miami Vice. Today, they’re small, compact, and ultra-portable. Ball grid arrays help make this possible by being the ideal solution for producing a miniature package more efficiently and effectively. With a PGA, as more and more pins were being soldered to a package, the unacceptable risk of bridging them was growing. BGA’s factory soldered to the package solved this problem, allowing for high density and reduced heat conduction.

However, there are disadvantages. One key disadvantage of BGA’s is the fact that solder balls on a ball grid array can not flex. This can lead to fracturing, but can also be alleviated by more effective design and compatibility between the substrate of the circuit board and the BGA. Many times, BGA’s require inspection and repair. This is done with special X-ray machines, microscopes, and industrial CT scanning machines.

After inspection, if a BGA is badly soldered or in need of repairs it can be removed at a rework station with an infrared lamp, a thermocouple, and a vacuum for lifting the package. This allows technicians to replace, refurbish, reball, and reinstall the BGA to return it to working order. Many times, because X-ray and CT Scan testing is cost prohibitive, the go-to solution for inspection and repair begins with electrical testing and boundary scanning – a method for testing the interconnects on a printed circuit board or integrated circuit.

Regardless, ball grid arrays are responsible for many of the compact electronics you use today. Chances are, if you were to violently throw your laptop into oncoming traffic, one of the pieces you would recover would be a ball grid array. While it’s not a recommended course of action, it simply goes to show how widespread BGA assembly and repair is.