BGA assembly refers to the assembly of printed circuit boards (PCBs) that use Ball Grid Array (BGA) components. BGA components are a type of surface mount device (SMD) that have small solder balls located on the bottom of the component instead of pins or leads. BGA assembly is a specialized form of SMT assembly that requires careful attention to detail during the production process.

BGA assembly is a specialized form of SMT assembly that requires careful attention to detail during the production process. By using BGA components, designers can achieve higher component density and better electrical performance, but also need to consider additional factors such as thermal management and inspection techniques.

Classification of BGA assembly:

BGA assembly can be classified into 3 types based the permutation way of solder balls: 

1. Surrounding Type Array-A surrounding type array is a type of BGA (Ball Grid Array) package that has a ring or border of solder balls around the periphery of the component. The surrounding type array is also known as a perimeter array or peripheral array. In a surrounding type array, the solder balls are arranged in a ring or border around the edge of the component, with no balls in the center. The surrounding type array provides several advantages over a standard or uniform BGA array. Surrounding type arrays are commonly used in high-performance applications, such as networking, telecommunications, and computing systems, where high I/O counts, signal integrity, and thermal performance are critical.
2. Staggered Type Array-A staggered type array is a type of BGA (Ball Grid Array) package that has a non-uniform or staggered arrangement of solder balls on the underside of the component. In a staggered type array, the solder balls are arranged in two or more rows, with the balls in one row offset or staggered relative to the balls in the adjacent row. Staggered type arrays are commonly used in high-performance applications, such as telecommunications, networking, and computing systems, where thermal performance, signal routing, and reliability are critical.
3. Full Array-Full array is a type of BGA (ball grid array) configuration in which the solder balls are arranged in a full grid pattern, with each ball located at a uniform distance from its neighbors. This type of configuration offers a high level of connectivity and is particularly suitable for applications with high pin counts and complex routing requirements.  Full array BGAs are commonly used in a wide range of electronic devices, including computers, networking equipment, consumer electronics, and industrial equipment. They are particularly well-suited for use in devices with high-speed data transfer requirements, such as microprocessors, memory chips, and graphics processing units.