Samsung Electronics Co. Ltd. in Seoul announced development of a 32-megabit memory replacement of SRAMs, using a low-power storage cell based on a single transistor and one capacitor--similar to a DRAM. Samsung claimed its new Uni-transistor RAM (UtRAM) is fully compatible with low-power SRAMs now used in mobile phones. Samples of the 32-Mbit memory are being shipped to customers, said the South Korean company.

Also today, Infineon Technologies AG in Munich and Micron Technology Inc. in Boise, Idaho, announced competing low-power synchronous DRAMs for battery-operated handheld systems. Infineon said its 128-Mbit Mobile-RAM will become available in the second quarter of 2001, while Micron said it is now sampling its first 64-Mbit BAT-RAMs with higher densities planned later this year.

Infineon's first Mobile-RAM is organized 8-Mbit-by-16 and housed in a chip-scale package--a fine-pitch ball-grid array (BGA) with a footprint of 8-by-9 mm, about a third the size of TSOP packages used for conventional DRAMs. The Mobile-RAM memory array operates on 2.5 volts and the I/O section uses 1.8 or 2.5 volts, said Infineon.

Meanwhile, Micron rolled out a 2-Mbit-by-32 memory, which operates on 3.3 or 2.5 volts in portable systems. Micron's BAT-RAM memories have a new feature, called temperature compensated self refresh (TCSR). When enabled and programmed by the system, TCSR allows the part to adjust refresh rate and power consumption based on temperature. At normal room temperatures, this feature allows the devices to consume even less power, said Micron.

"Because BAT-RAM is specifically designed for mobile and wireless applications, it will consistently provide the smaller form factor, low-power specs, and features these products need," said Phil Martin, DRAM market development manager at Micron in Boise.

Focused on third-generation (3G) cellular phones, Samsung's new 32-Mbit UtRAM operates on an active current of 30 milliamperes with a standby mode using 200 microamperes and a power-down mode at 10 microamperes. The Korean chip supplier said the new memory chip will replace SRAMs in next-generation phone designs without circuit alterations. The company said standard SRAMs with six-transistor cells are unable to easily achieve the memory capacity required by these future multimedia devices.

In May, Japan is scheduled to begin third-generation cellular phone service, using the wide-band code-division multiple access (W-CDMA) format. Samsung said the new W-CDMA handsets will require at least 30 megabits of memory, setting the stage for its new UtRAM to take off as a replacement to low-power SRAMs.

Samsung said industry analysts are now predicting that worldwide shipments of mobile phones will reach 520 million units in 2001, with one billion handsets expected to be sold in 2004.

With battery systems becoming a prime applications for low-power DRAMs, new industry standards are now being defined by the Joint Electronic Devices Engineering Council, said Desi Rhoden, director of the JEDEC board. And Micron promises to follow "any standards set" by JEDEC, said Gary Welch, DRAM product marketing manager at the Boise company.

Meanwhile, Infineon said it is also working with partners in the industry to set standards. The company is also working with JEDEC to standardize the 54-ball FBGA package used on its Mobile-RAM. Infineon said it hopes other suppliers will second source its format to help drive up higher volumes for low-power DRAMs.

"This new 128-Mbit device is the first product on our Mobile-RAM roadmap, which will soon be extended to the 256-Mbit generation," said Heinrich Florian, director of product marketing of Infineon's Memory Product Division.

Infineon said personal digital assistants (PDAs) are the largest target markets for Mobile-RAM devices. In 2000, about 10 million PDAunits where shipped worldwide, according to the Munich chip maker. Infineon said Dataquest analysts are predicting that PDA unit volumes will grow 46% per year to 34 million units in 2004.

Samsung, Micron, and Infineon did not release pricing on their products today.