Siemens 6ES7954-8LC03-0AA0 SIMATIC Memory Card

Siemens 6ES7954-8LC03-0AA0 SIMATIC Memory Card is a 4 MB MMC memory card that uses 3.3 V flash to provide persistent storage for SIMATIC S7-1x00 CPU/SINAMICS configurations. Designed as a genuine spare part for the S7-1x00 family, it installs in the CPU’s memory-card slot and holds PLC program blocks, configuration data, and other non-volatile information needed for operation when power is removed. The 4 MB capacity and 3.3 V flash technology are characteristic of this memory card generation, and Siemens lists this exact part number as a spare part with a documented successor: 6ES7954-8LC04-0AA0. This card is typically used to expand or replace memory in S7-1000 CPUs, facilitating program transfer and data archival across devices within Siemens’ SIMATIC ecosystem.