dynamic random-access memory

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Figure 6: The increasing capacity of dynamic random-access memory (DRAM) chips.

NMOS circuit implementation of (A) a DRAM cell, (B) an SRAM cell, and (C) an EPROM transistor, where the charge is stored on the floating gate. The address line selects the cell to be written or read, and the memory-state information is sensed on the bit line(s).

dynamic random-access memory

electronics

Also known as: DRAM, dynamic RAM

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June 25, 2026

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Figure 6: The increasing capacity of dynamic random-access memory (DRAM) chips. — Figure 6: The increasing capacity of dynamic random-access memory (DRAM) chips.

Dynamic random-access memory (DRAM) is a type of computer main memory that requires a constant power supply and periodic rewriting to retain data. Unlike static RAM (SRAM), which stores data in flip-flops as long as power is supplied, DRAM stores each bit in an electrical capacitor. This design makes DRAM storage cells smaller than SRAM, allowing for more memory on a single chip, though access times are slower.123

Because capacitors in DRAM gradually leak charge, the stored data must be refreshed approximately 50 times per second to maintain its integrity. Despite this, DRAM is commonly used for main memory due to its higher storage density compared to SRAM.23

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computer
Main memory
…gradually decays, IC memory is dynamic RAM (DRAM), which must have its stored values refreshed periodically (every 20 milliseconds or so). There is also static RAM (SRAM), which does not have to be refreshed. Although faster than DRAM, SRAM uses more transistors and is thus more costly; it is used…
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…gradually decays, IC memory is dynamic RAM (DRAM), which must have its stored values refreshed periodically (every 20 milliseconds or so). There is also static RAM (SRAM), which does not have to be refreshed. Although faster than DRAM, SRAM uses more transistors and is thus more costly; it is used…
Read More

Intel
1970s–1980s: Early products and IBM partnership
…one-kilobit dynamic random-access memory (DRAM) chip, was successful and the first chip to store a significant amount of information. It was purchased first by the American technology company Honeywell Incorporated in 1970 to replace the core memory technology in its computers. Because DRAMs were cheaper and used less power…
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…one-kilobit dynamic random-access memory (DRAM) chip, was successful and the first chip to store a significant amount of information. It was purchased first by the American technology company Honeywell Incorporated in 1970 to replace the core memory technology in its computers. Because DRAMs were cheaper and used less power…
Read More

capacitor dielectric and piezoelectric ceramics
Random-access memories
…in dynamic random-access memories (DRAMs). They also can be used as ferroelectric random-access memories (FERAMs), where the opposing directions of polarization can represent the two states of binary logic. Unlike conventional semiconductor RAM, the information stored in FERAMs is nonvolatile; i.e., it is retained when the power is turned…
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…in dynamic random-access memories (DRAMs). They also can be used as ferroelectric random-access memories (FERAMs), where the opposing directions of polarization can represent the two states of binary logic. Unlike conventional semiconductor RAM, the information stored in FERAMs is nonvolatile; i.e., it is retained when the power is turned…
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Robert H. Dennard
…of the one-transistor cell for dynamic random-access memory (DRAM) and with pioneering the set of consistent scaling principles that underlie the improved performance of increasingly miniaturized integrated circuits, two pivotal innovations that helped spur more than three decades of growth in the computer industry.
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…of the one-transistor cell for dynamic random-access memory (DRAM) and with pioneering the set of consistent scaling principles that underlie the improved performance of increasingly miniaturized integrated circuits, two pivotal innovations that helped spur more than three decades of growth in the computer industry.
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