The Realtek RTS5227 is a PCI Express card reader controller commonly integrated into laptops and desktop systems for managing flash memory card interfaces. It supports multiple card formats, including SD, SDHC, SDXC, and MMC, enabling fast and reliable data transfer for storage expansion and media access. Connected via the PCIe interface, it offers improved bandwidth and lower latency compared to older USB-based readers. The RTS5227 is widely supported across Windows and Linux operating systems through Realtek drivers. Its compact design and low power consumption make it ideal for portable devices, providing stable performance for everyday file transfers, photography workflows, and multimedia use.