The CY15B104QSN-108LPXI is a 4-Mbit EXCELON™ Ultra Ferroelectric RAM (F-RAM) with quad SPI, organized as 512K × 8 and supporting up to 108 MHz SDR and 54 MHz DDR. It delivers instant non-volatile writes, high endurance, and 151-year data retention at 65°C. Operating from 1.8 V to 3.6 V over -40°C to +85°C, it features low power, ECC/CRC, write protection, and a 256-byte special sector. The 8-pin GQFN package is RoHS compliant and not recommended for new designs.