What is DDR PHY?

A DDR PHY (Double Data Rate Physical Layer) is the physical interface that connects a memory controller to DDR SDRAM (Double Data Rate Synchronous Dynamic Random-Access Memory). It handles the complexities of DDR signaling, including timing, voltage levels, and impedance matching, ensuring reliable data transfer between the memory controller and the DDR memory chips. It is a crucial component in systems requiring high-bandwidth memory access, such as computers, mobile devices, and graphics cards.