Why is SRAM more expensive and less space-efficient than DRAM?

SRAM (static random access memory) is more expensive and less space-efficient than DRAM (dynamic random access memory) primarily due to its complex internal architecture.

• Complexity and Size: An SRAM cell is composed of a flip-flop circuit that requires four to six transistors to store a single bit. In contrast, a DRAM cell stores each bit using only one transistor and one capacitor. Because DRAM requires significantly fewer electrical components, its storage cells are much smaller, allowing a single chip to hold several times more data than an SRAM chip of the same physical size.123
• Cost: Due to the higher number of transistors required for each bit, SRAM is more complex to manufacture and occupies more space on a silicon wafer, which increases its cost relative to the simpler, more compact DRAM.23

While DRAM is more space-efficient and cost-effective for main memory, it is slower because it requires periodic refreshing to maintain its charge. SRAM is used for cache memory and CPU registers because it provides much faster access speeds and does not require refreshing.123