White Paper: Electronics & Computers

A Guide to Ball Grid Arrays


The ball grid array (BGA) is a surface-mount chip package that is used to mount embedded devices (e.g., microprocessors) by melting balls of solder between the face of the device and the circuit board. Unlike the perimeter-only package type, which places soldering pins along the edge of the device, a BGA aligns its solder balls in a grid beneath the bottom surface of the device. As a result, this approach leaves a considerably smaller footprint on the PCB and induces better thermal and electrical properties than a perimeter-style mounting package. It is no surprise the format’s popularity has grown in tandem with the continuous miniaturization of electronics.

And yet, BGAs are the boon and bane of engineers and printed circuit board designers the world over. Their unparalleled pin density and low lead inductance are essential in today’s high pin count, high-frequency integrated circuits. However, that same pin density and unique interface create a challenge unique unto themselves. While there are entire textbooks that cover the topic of BGAs, their use, and fanout techniques, the quick overview provided here offers an engineer a good starting point for using BGAs in designs.

Topics covered in this BGA guide include: BGA basics, using BGAs with vias, soldering of BGAs, testing of BGAs, and the overall limitations of BGAs.

Don't have an account? Sign up here.