The Curtiss-Wright / VMETRO / Micro Memory MM5425/512M is a battery-backed PCI NVRAM module that preserves critical data during power loss while accelerating I/O performance in mission-critical systems. Built around 512MB of high-speed SDRAM coupled with redundant on-board lithium-ion batteries, this card replaces slower disk accesses with memory-speed writes—delivering burst transfer rates up to 533 MB/s. The module interfaces via 64-bit / 66MHz PCI 2.2 or PCI-X and operates under direct host control, eliminating the overhead penalty of external storage controllers. This architecture excels in journaling file systems and NFS environments where frequent small writes would otherwise degrade disk performance. EDAC protection maintains data integrity, while specialized Mailbox DMA optimizes both read and write transfers. Battery status registers, software-programmable status LEDs, and automatic failover circuitry provide complete power management visibility and protection. System-level integration means the host retains full control over the file system, making the MM5425/512M ideal for file servers, storage appliances, critical data logging, industrial control systems, military and aerospace platforms—any application where synchronous write latency and data persistence are non-negotiable.
## Technical Specifications
• **Capacity**: 512MB NVRAM (also available in 256MB, 1GB, 2GB)
• **Interface**: 64-bit / 66MHz PCI 2.2, PCI-X
• **Memory Technology**: SDRAM with Non-Volatile backup
• **Data Retention**: Two on-board redundant lithium-ion batteries
• **Burst Transfer Rate**: Up to 533 MB/s
• **Error Handling**: Error Detection and Correction (EDAC)
## Key Features
• Specialized Mailbox DMA for maximized read/write throughput
• Minimized latency for I/O-intensive workloads
• Interrupt support with device drivers across multiple operating systems
• Battery status monitoring via CSR (Control and Status Register)
• Software-programmable status LEDs
• Automatic battery failover circuitry
## Typical Applications
• File servers and NFS-based storage appliances
• Journaling file system metadata logging
• Mission-critical data retention during power interruptions
• Industrial control, military, and aerospace systems requiring persistent storage
• High-frequency synchronous write environments
## Compatibility & Integration
Fully host-controlled with PCI 2.2 and PCI-X compatibility. Device drivers available for multiple operating systems. No external storage controller dependency.
