Siemens 6ES5-375-1LA61 Memory Submodule is a CMOS EPROM-based memory module for SIMATIC S5 PLCs, providing 64K x 8-bit storage to extend program memory on compatible CPUs. It is designed for S5 systems in the 375-series family, and Siemens documentation notes a maximum usable memory of 48 KBytes when this submodule is installed (for example with the S5-115U). The official part number is 6ES5-375-1LA61 and it is marketed specifically as a memory submodule for the S5 375 configuration.
