Siemens 6ES7954-8LL03-0AA0 PLC CPU Module — Legacy Replacement. Siemens 6ES7954-8LL03-0AA0 is the exact manufacturer order number for a plc cpu module in the SIMATIC S7-300 Connection System portfolio. Siemens describes this exact reference as: *** spare part *** SIMATIC S7, memory cards for S7-1x00 CPU, 3, 3 V flash, 256 MB. The verified manufacturer lifecycle record is PM410:Product cancellation.