What is LGA
LGA (Land Grid Array) is a type of IC package commonly. Unlike other package types such as PGA (Pin Grid Array) or BGA (Ball Grid Array), LGA packages have pins on the socket instead of on the IC itself. This means that the IC package features a grid of contact points, known as “lands,” on its underside. These lands make contact with corresponding pins on the socket or can be directly soldered onto the PCB.
Not all grid rows and columns need to be used, allowing manufacturers to optimize the package layout for specific requirements. The lands can be created using solder paste or LGA sockets, and they can have different shapes and sizes, such as rectangular, triangular, or circular. Some LGAs even have a honeycomb appearance.
When designing LGAs, manufacturers consider factors like matching spring contacts, contact likeness, and proper electrical distance to nearby contacts. These optimizations ensure reliable and efficient electrical connections between the IC package and the PCB.