Memory card

Lore & Background

The basis for memory card technology is flash memory. The development of memory cards was driven in the 1980s by the need for an alternative to floppy disk drives that had lower power consumption, had less weight and occupied less volume in laptops. Some were also marketed as a lower cost alternative to ROM cartridges. Several competing and incompatible memory card formats were developed by various vendors, such as the Bee Card, Astron SoftCard, Sega Cards, NEC UltraLite memory cards, and the Mitsubishi Melcard. The Sega Card was developed as a cheaper alternative to game cartridges. Some memory cards were used for memory expansion in laptops. This format later included support for other devices besides memory cards. PC Card was among the first commercial memory card formats to come out, but is mainly used in industrial applications and to connect I/O devices such as modems. Some early memory cards used SRAM as a storage medium, which required a lithium battery to keep the contents in the SRAM. These cards were faster than their flash counterparts. Other early cards such as the Bee Card contained non-modifiable ROM, Write once read many EPROM or rewriteable EEPROM memory. In 1994, memory card formats smaller than the PC Card arrived. The first one was CompactFlash and later SmartMedia and Miniature Card. The desire for smaller cards for cell-phones, PDAs, and compact digital cameras drove a trend that left the previous generation of 'compact' cards looking big. In 2000 the SD card was announced. SD was envisioned as a single memory card format for several kinds of electronic devices, that could also function as an expansion slot for adding new capabilities for a device. In industrial and embedded fields, even the venerable PC card (PCMCIA) memory cards still manage to maintain a niche, while in mobile phones and PDAs, the memory card has become smaller. The Microdrive had higher capacities than memory cards at the time. All three concepts became obsolete once flash memory prices became lower and their capacities became higher by 2006. New products of Sony (previously only using Memory Stick) and Olympus (previously only using XD-Card) have been offered with an additional SD-Card slot beginning in 2010. Effectively, the format war has turned in SD-Card's favor. By the late 2010s, newer high-speed formats such as CFexpress and Universal Flash Storage (UFS) emerged to meet the demands of 4K, 8K, and RAW video recording, as well as high-speed continuous photography. XQD cards, once positioned as a successor to CompactFlash, have largely been replaced by CFexpress Type B, which shares the same physical form factor but uses a faster PCIe interface.

Reader's Guide

Memory cards have been a pivotal technology in the evolution of portable digital storage, enabling the expansion of memory in devices ranging from digital cameras to early game consoles like the Neo Geo. Their development was driven by the need for a compact, low-power alternative to floppy disk drives in laptops, and they also served as a cheaper alternative to ROM cartridges. The history of memory cards is marked by a series of competing and incompatible formats, including PC Card, CompactFlash, SmartMedia, Memory Stick, and SD cards, with SD cards emerging as the most common type by 2024. The format war gradually resolved in favor of SD cards, as evidenced by Sony and Olympus adding SD card slots to their products in 2010. The introduction of high-speed formats like CFexpress and UFS in the late 2010s addressed the demands of high-resolution video and photography. Despite the rise of internal storage in modern smartphones, memory cards remain widely used in action cameras, drones, e-readers, and other portable devices, and continue to be essential in industrial and embedded applications.

Did You Know?

• Some early memory cards used SRAM as a storage medium, which required a lithium battery to keep the contents in the SRAM.