Siemens 6ES5375-1LA21 Memory Module

Engineered for SIMATIC S5 Program and Data Storage

This module stores user programs and runtime data securely. It provides read-write memory for the Siemens 6ES5375-1LA21 unit. You will find this RAM card in SIMATIC S5 CPUs and expansion units. Unlike EPROM modules, this version supports online program changes. It retains all data using an internal lithium battery.

Technical Specifications & Physical Dimensions

We designed this memory module for flexible program management. The table below presents all verified technical specifications.

Parameter	Specification
Memory Capacity	32 KB (256 Kbit)
Memory Type	Static RAM (battery-backed)
Package Type	28-pin DIP (dual in-line)
Physical Dimensions	38mm x 14mm x 9mm
Total Weight	12 grams
Operating Voltage	5V DC (±5%)
Access Time	200 nanoseconds maximum
Backup Battery	Lithium (integrated, non-replaceable)

Functional Architecture and Data Handling

This RAM module plugs directly into the S5 CPU memory socket. It allows both read and write operations during run mode. You can modify program logic without erasing the chip. Moreover, the module includes an onboard lithium battery for backup. This component retains data for up to 5 years without external power. Consequently, the CPU preserves programs during extended maintenance shutdowns.

Installation and Operational Guidelines

The Siemens 6ES5375-1LA21 requires no UV eraser for reprogramming. It automatically switches to battery backup when the system powers down. You must align pin 1 with the socket marker carefully. Always handle the module with anti-static precautions. This practice prevents electrostatic discharge damage to the CMOS memory. Furthermore, the module includes a battery status monitoring feature. This function warns operators before the battery reaches end-of-life.

Physical Characteristics and Environmental Limits

This memory module features a standard plastic DIP package. Its lightweight 12 gram design allows for easy replacement. The layout follows Siemens standard memory module specifications. Therefore, it fits securely into any S5 CPU memory socket. The module retains data without external power connections. In addition, it maintains stable operation between 0°C and 60°C ambient temperature. You can store this module safely between -25°C and 70°C.