Cpu Socket Types Used In Motherboard : Pga & Bga Sockets
3. PGA socket : it is a type of integrated circuit packaging. In a PGA, the package is square or rectangular, and the pins are arranged in a regular array on the underside of the package. The pins are commonly spaced 2.54 mm (0.1") apart, and may or may not cover the entire underside of the package.
PGAs are often mounted on printed circuit boards using the through hole method or inserted into a socket. PGAs allow for more pins per integrated circuit than older packages such as dual in-line package (DIP). The below figure shows the pin grid array at the bottom of a XC68020, a prototype of the Motorola 68020 microprocessor
4. BGA sockets : A Ball Grid Array (BGA) is a type of surface-mount packaging used for integrated circuits. BGA packages are used to permanently mount devices such as microprocessors. The BGA is descended from the pin grid array (PGA), which is a package with one face covered (or partly covered) with pins in a grid pattern which, in operation, conduct electrical signals between the integrated circuit and the printed circuit board (PCB) on which it is placed.Soldering of BGA devices requires precise control and is usually done by automated processes. BGA devices are not suitable for socket mounting.A disadvantage of BGAs is that the solder balls cannot flex in the way that longer leads can, so they are not mechanically compliant.
The example for the BGA is as shown in the below figure: