DRAM vendors redesign market strategies

DDR3 will account for 72 percent of DRAM sales by 2011, analysts say

Despite an oversupply that has led to severe price erosion over the past year, DRAM makers are determined to pursue the latest innovation to achieve an edge over their competitors. Leading vendors are expanding their product lines, reducing operating costs and enhancing production efficiencies to mitigate ongoing problems in the mainstream DRAM market.

To sustain bit demand is to increase the adoption of more complex OS, primarily Microsoft Corp.'s Vista, and an ongoing transition from desktops to notebooks. These new systems need not only higher densities of main memory, but discrete memory and GPUs to deliver adequate performance. In many cases, DRAM makers achieve these goals with the launching of a new generation of DDR3 devices tailored to supplant earlier generation of DDR2 memories. Analysts at market research firm IDC expect DDR3 memories to account for 72 percent of the total DRAM market by 2011.

Tokyo-based Elpida Memory, for example, uses an optimized copper interconnect process and new circuit technology to provide the industry's first DDR3 SDRAM that can operate up to 2.5Gbit/s. The 1Gbit device is available at the industry standard 1.5V. But the company is also offering a 1Gbit DDR3 device that operates at 1.8Gbit/s at 1.2V. The copper interconnects give superior transmission characteristics over aluminum options.

The quest for power efficiency
The recent spike in energy costs has designers of both servers and desktops refocusing their efforts to reduce power usage in the main system memory. With memory using as much as 15 percent of all power in datacenter server designs and the number expected to rise as new application drive memory requirements are up, manufacturers are putting renewed priority on developing more power-efficient parts. Micron Technology, for example, has expanded its energy-efficient Aspen product portfolio with more efficient low-voltage DDR2 and DDR3 products.

"Higher energy efficiency is very essential in datacenters that run 24/7," said Brian Shirley, VP, memory group, Micron. "Until recently, IT and datacenter managers primarily searched for ways to reduce power use with energy-efficient processors and power supplies, but they hadn't looked at the added savings they can achieve with low-voltage memory," he added.

Early this year, Micron released 2Gbit-based DDR2 modules operating at 1.5V, and 1Gbit-based DDR3 modules operating at 1.35V. The new 8Gbyte DDR2 modules minimize power use by up to 58 percent compared with conventional 1Gbit-based 1.8V DDR2 modules. The new DDR3 server modules, available in densities up to 4Gbyte, use 21 percent less power than standard 1.5V, 1Gbit-based DDR3 modules. To achieve better systems and graphics performance, the new DDR3 modules back data rates up to 1,333Mbit/s.

Conserving energy
Lower power use is also the main focus in embedded and mobile applications. Memory-intensive applications such as data-connected 3G phones, personal media players and GPS systems are driving the migration from older low-power DDR1 (LPDDR1) ICs to a new generation of LPDDR2 devices. Both Elpida and Hynix Semiconductor announced LPDDR2 ICs within the past year, for example. The 1Gbit Hynix part, fabricated in a new 66nm process, supports a maximum operating speed of 800Mbit/s off a 1.2V supply. It comes in a compact 9mm x 12mm form factor.

Pushing to the limits
Meanwhile, DRAM makers continue to push the process envelope to higher densities. Using a 50nm process, industry leader Samsung Semiconductor recently announced the industry's smallest 2Gbit DDR3 devices. The tiny form factor helps designers configure up to 8Gbyte of memory chips for Rambus inline memory modules, and up to 4Gbytes for small outline DIMMs and unbuffered DIMMs without stacking. Using dual-die packages, 2Gbit DDR3 RIMMs can reach densities of 16Gbyte. The new 2Gbit IC also uses up to 40 percent less power than dual-chip solutions using two 1Gbyte memory devices. Data rates reach up to 1.3Gbit/s at 1.5V or 1.35V.

- John Mayer
EE Times