Quad Flat Pack is a square package with leads on all four sides. The leads have a gull wing shape and have a narrow spacing. The spacing varies accor0ding to the actual chip. These components are damaged easily hence it is required to handle with great care. The main measurement for QFPs is coplanarity, which is established when the first lead from the component is placed on the PCB board. The coplanarity standard is ±4 mils.
A Quad Flat Pack
The Pin Grid Array or PGA is a type of packaging used for integrated circuits. PGA uses an array of leads as the means of providing external electrical interconnection. Normally, the PGAs are used with through-hope PCBs. PGAs accommodate higher density packages that are common with 32-bit microprocessors.
Ball Grid Array utilizes an array of metal spheres or balls for providing external electrical interconnection. The balls are composed of solder, and are attached to a laminated substrate at the bottom side of the package. The die of the BGA is connected to the substrate either by wirebonding or flip-chip connection. The substrate of BGA has internal conductive traces that route and connects the die-to-substrate bonds to the substrate-to-ball array bonds.