Infineon, Micron team up on pseudostatic RAM for cell phones

By EETimes News Services
iApplianceWeb
(06/24/02, 12:40:16 PM EDT)

NEW YORK - Slowly but surely, as the computing paradigm shifts from a desktop- and enterprise-centric focus to a more distributed small footprint net-centric iappliance and embedded networking modality, memory architectures and technologies are changing also.

The newest example of this shift is the announcment this week that Infineon Technologies AG and Micron Technology Inc. have joined forces to develop a low-power pseudostatic RAM targeted at high-data-rate 2.5G and 3G cellular phones. Dubbed CellularRAM, the first device will be available by the end of this year, with others to follow during the first half of 2003.

The push for cell phones that incorporate data-transfer functionality and a greater range of applications has created demand for fast, higher-density memories, providing a seed market for products such as CellularRAM, the companies said. Using a pseudostatic RAM architecture that uses a single-transistor DRAM cell rather than a six-transistor SRAM cell, the CellularRAMs will help GPRS and UMTS phone makers add more bells and whistles to their units while maintaining system speed and a compact form.

CellularRAM will be pin compatible with SRAM, allowing them to be used as drop-in replacements for the asynchronous SRAM currently used in many cell phone designs. The devices will also employ a burst read and write mode that emulates a flash memory interface. Bandwidth runs at 210 Mbytes per second, based on a maximum clock rate of 108 MHz. Initial latency is 60 nanoseconds.

Micron and Infineon have worked together before in hopes of setting standards for memory designs in application-specific devices. Last year, Infineon put the finishing touches on a new class of low-latency DRAM aimed at the networking market. Micron licensed the device, known as the reduced latency DRAM, and both companies are now sampling the device, with the hope of a ramp-up next year.

The companies have also released earlier versions of low-power DRAM aimed at cell phones and other mobile devices. Neither company has gained traction in the stagnant cell phone market or with an industry that has been slow to deliver on promises of high-data-rate cellular networks, which many expect would spur new designs that could use the lower-power memories.

Both companies will face similar problems with CellularRAM, as there are relatively few GPRS and UMTS phones in the market. But a huge growth opportunity remains once telecommunications companies and phone makers smooth the so-far bumpy transition to high-data-rate networks, the memory makers said.

Infineon and Micron will first make a 32-Mbit device in a 2-Mbit x 16 configuration, which will come out in late 2002. Then 16-Mbit and 64-Mbit devices, both in x 16 configurations, will come out in the first half of 2003. CellularRAM devices will be powered from a single 1.8-volt supply and offer 2.5V and 3.0V I/O voltage options.