A Short Course on DRAMs

They look like tiny metal spiders with spindly wire legs. And everyone, it seems, wants them--right now.

They are DRAMs, short for dynamic random access memory chips, the heart of a computer’s memory system. And they are in very short supply these days. Analysts estimate that manufacturers worldwide will sell about 1.2 billion of the chips this year, and could easily sell as many as 250 million more, if they had them.

But the shortage in the United States, fueled by declining Japanese DRAM exports and increased U.S. computer production, has electronics manufacturers scurrying for supplies while fueling tension in the industry. For example, Atari Corp., the Silicon Valley video game maker, sued Micron Technology this month in a dispute over whether promised chips were being delivered at contracted prices.

DRAMs allow computers and other electronic devices to store bits of data for quick retrieval. In computers, DRAMs are the main memory bank and are typically used to store software programs and the machine’s operating instructions. A secondary memory source is a floppy or hard disk.

The most common DRAM chips these days can store up to 256,000 bits of data on a piece of silicon smaller than a postage stamp. But the industry is increasingly turning to the one megabit DRAM, a chip that can hold as many as 1 million bits of information.

When they were invented in the 1970s by Intel, DRAMs held only 1,000 bits of information. Nevertheless, because they allowed quick access to stored information, they became an instant hit. These days DRAMs are increasingly being used in automobiles, household appliances, “smart” credit cards, televisions and videocassette recorders.