Samsung Electronics announced at its Mobile Solution Forum last week that it now offers a 32-Gbyte NAND flash-based solid-state disk (SSD) for mobile PCs. This marks the first time that NAND flash has moved into mobile computing applications.
The 1.8-in. SSD weighs 15 g. It has a read/write speed of 57 and 32 Mbytes/s, respectively, and consumes 0.1 W in power-down and 0.5 W when the device is in use. Also, its endurance temperature ranges from –20°C to 80°C. By comparison, a 1.8-in. hard-disk drive with similar memory capacity weighs 61 g, has a read/write speed of 15 Mbytes/s, consumes 1.5 W, and has an endurance temperature of 0°C to 60°C.
Don Barnetson, associate director of marketing for flash memory at Samsung Semiconductor Inc., said his company is targeting the sub-notebook market because some users would be willing to trade off density for speed, power savings, and reliability.
"When you look at the reliability, power savings, and performance of the SSD, it makes sense," Barnetson said, adding that 8 to 16 Gbytes of SSD is enough to carry user applications and data. "In a notebook, these things are critical."
The cost of NAND flash memory has been declining by approximately 40% each year over the past 10 years. As the price continues to decrease, Barnetson said, the storage medium will enter more consumer markets.
While hard drives are still more cost-effective than NAND flash, Barnetson said that 4-Gbyte SSDs have reached cost parity with hard drives. Samsung sees the overall global SSD market surging from $540 million in 2006 to $4.5 billion by 2010.
NAND flash memory outperforms traditional hard drives in a number of ways. First, the SSD uses just 5% of the electricity needed to power a hard-disc drive. It’s also noiseless. And, it’s more durable.
"The beauty of this product is that it looks and feels like a hard drive to the outside world," Barnetson said. "It requires very little design work," so it should be relatively easy for engineers to include them in their designs.
Electronic Design Analysis
By Bill Wong
Samsung is quite correct about SSDs changing the way devices are being designed. Previously, the boundary for built-in flash in hand-held devices was about 16 Mbytes, and the mass storage boundary was about 8 to 16 Gbytes. Samsung’s 32 Gbyte SSD hits well above this mark. That will likely push hard disk drive (HDD) solutions out of the way over the next year or so, as they have done in the MP3 player market where HDDs are only found above 4 Gbytes.
SSDs have the edge in almost all areas compared to HDDs except two: capacity and price. It is now up to the designer to balance these tradeoffs for their application. SSDs work well in deeply embedded applications where their low power and high reliability are especially desirable.