/ˈɛsˌræm/
noun … “High-speed, volatile memory with no refresh needed.”
SRAM (Static Random Access Memory) is a type of volatile memory that stores data using bistable latching circuitry instead of capacitors, unlike DRAM. This design allows SRAM to retain data as long as power is supplied, without requiring periodic refresh cycles, resulting in faster access times. SRAM is commonly used for CPU cache, small buffers, and other performance-critical applications where speed is more important than density or cost.
Key characteristics of SRAM include:
- Volatile: loses data when power is removed.
- No refresh needed: data is stable while powered.
- Fast access: typically faster than DRAM, ideal for caches and registers.
- Low density and higher cost: fewer bits per unit area compared to DRAM.
- Integration: often embedded close to the CPU for ultra-low latency access.
Workflow example: Using SRAM as a CPU cache:
cache_line[4] = SRAM.read(address)
cache_line[2] = 42 -- Modify cached value
SRAM.write(address, cache_line) -- Write back to memory if needed
Here, SRAM serves as a temporary high-speed storage near the CPU, enabling rapid reads and writes for performance-critical operations.
Conceptually, SRAM is like a set of drawers next to your workstation: items can be retrieved and stored almost instantly, but they disappear if the power is turned off.
See Memory, DRAM, Cache, CPU, Memory Management.