Overview
A pin grid array (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 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).
Chip mounting
The chip can be mounted either on the top or the bottom (the pinned side). Connections can be made either by wire bonding or through flip chip mounting. Typically, PGA packages use wire bonding when the chip is mounted on the pinned side, and flip chip construction when the chip is on the top side. Some PGA packages contain multiple dies, for example Zen 2 and Zen 3 Ryzen CPUs for the AM4 socket.
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