 thumb|350px|close up to the pins of a pin grid array   a pin grid array, often abbreviated pga, 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&nbsp;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). ==pga variants== ===plastic===  plastic pin grid array (ppga) packaging was used by intel for late model mendocino core celeron processors based on socket 370. some pre-socket 8 processors also used a similar form factor, although they were not officially referred to as ppga.  ===flip chip=== thumb|right|the underside of a fc-pga package (the die is on the other side) a flip-chip pin grid array (fc-pga or fcpga) is a form of pin grid array in which the die faces downwards on the top of the substrate with the back of the die exposed. this allows the die to have a more direct contact with the heatsink or other cooling mechanism. the fc-pga was introduced by intel with the coppermine core pentium iii and celeron processors based on socket 370, and was later used for socket 478-based pentium 4 and celeron processors. fc-pga processors fit into zero insertion force (zif) socket 370 and socket 478-based motherboard sockets; similar packages have also been used by amd. it is still used today for mobile intel processors. ===staggered pin=== the staggered pin grid array (spga) is used by intel processors based on socket 5
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