STMicroelectronics M27C4002-12F1 EPROM Memory

STMicroelectronics M27C4002-12F1 EPROM Memory is a 4-megabit parallel EEPROM (EPROM) organized as 256K × 16 and housed in a 40-pin windowed DIP. This UV-erasable device belongs to the M27C4002 family and is available in windowed UV-erasable and OTP variants, offering flexible programming options for firmware storage and data tables in embedded systems. The -12F1 timing grade provides a 120 ns read access time, and the device operates from a 5 V supply with a higher programming voltage required for writes, typical for UV EPROM parts. Suitable for use in equipment that employs parallel 16-bit data paths and needs non-volatile program memory, it is commonly used for boot code, firmware libraries, and firmware updates in vintage to mid-range embedded boards. STMicroelectronics’ M27C4002 devices are designed to fit standard EPROM sockets and 16-bit data buses, enabling straightforward replacement or cross-compatibility with related ST products.