flashRAM

FlashRAM is a non-volatile semiconductor memory that retains data without power. In common usage, the term is often used informally to refer to flash memory or flash storage, though standard terminology differentiates memory types. Flash memory stores information by trapping charge in floating-gate or charge-trap transistors and is electrically erasable and programmable, enabling data to persist through power cycles.

Two main architectures exist: NOR and NAND. NOR flash provides random access at the byte level and is suitable for code storage and small data areas. NAND flash offers higher density and lower cost per bit, organized in pages and blocks, with data erased in blocks. NAND is widely used in USB drives, memory cards, and solid-state drives, while NOR is common in embedded systems requiring fast random reads.

Key characteristics include non-volatility, high storage density, and solid-state reliability with no moving parts. However, write operations are constrained by erase requirements and finite program/erase cycles. Endurance depends on the memory type (SLC, MLC, TLC, QLC) and process node, typically ranging from thousands to tens of thousands of cycles. Modern devices employ wear leveling, bad-block management, error-correcting codes (ECC), and garbage collection to extend lifetime and performance. Data retention depends on temperature and usage, often lasting years under normal conditions.

Applications span consumer electronics, USB flash drives, memory cards, and solid-state drives, as well as embedded systems where compact, energy-efficient, non-volatile storage is essential. As density increases, flash memory remains a cornerstone of modern non-volatile storage, balancing cost, capacity, and endurance.