释义 |
static random-access memory
static random-access memory[′stad·ik ′rand·əm ¦ak‚ses ′mem·rē] (computer science) A read-write random-access memory that uses either four transistors and two resistors to form a passive-load flip-flop, or six transistors to form a flip-flop with dynamic loads, for each cell in an array. Once data are loaded into the flip-flop storage elements, the flip-flop will indefinitely remain in that state until the information is intentionally changed or the power to the memory circuit is shut off. Abbreviated SRAM. static random-access memory (storage)(SRAM) Random-access memory in which each bit ofstorage is a bistable flip-flop, commonly consisting ofcross-coupled inverters. It is called "static" because itwill retain a value as long as power is supplied, unlikedynamic random-access memory (DRAM) which must be regularlyrefreshed. It is however, still volatile, i.e. it will loseits contents when the power is switched off, in contrast toROM.
SRAM is usually faster than DRAM but since each bit requiresseveral transistors (about six) you can get less bits of SRAMin the same area. It usually costs more per bit than DRAM andso is used for the most speed-critical parts of a computer(e.g. cache memory) or other circuit. |