The Serial ATA is an inside-the-box storage interface with high cost-performance ratio.

Serial ATA has two pairs of lines, i.e. 4 lines (7 lines including ground connections). Each pair controls respective signals, one from controller to device and the other from device to controller. Therefore, there is no signal skew caused from signaling time difference as in parallel ATA.

The Serial ATA boasts a low voltage of 0.5V, one-tenths of the 5V parallel ATA. The low voltage reduces electromagnetic interference and power consumption rate during data transmission. Low power consumption is especially suitable for mobile products.

Serial ATA eliminates the need for a master/slave jumper by connecting hosts to individual devices in a point-to-point fashion. This enables users to use thin cables of 1 meter in length, providing more flexibility in contrast to the parallel ATA of cable length limitation. As well, the cable’s smaller size, only four lines, makes it easier to route inside the chassis of slim PCs. The simplified cables also improve air flow in the system and provide more convenience to users in routing cables.
Along with cables, connectors have also been simplified. The figure below shows that Serial ATA is comprised of a data cable and a power cable. The connector at the end of the thin, red data cable has seven pins, four controlling signal lines and three controlling ground connections. In case of power cable, one additional line is added to comprise five lines. 12V, 5V and 3.3V for each ground connection made of these five lines. 3.3V line was added to provide power directly when the voltage in the HDD circuit drops. As shown in the lower right figure, the previous ATA connector was relatively large with 40 pins whereas Serial ATA offers slimmer connectors suitable for 2.5” HDD used in laptop PCs. In other words, since the connector is designed with common standard for both 3.5” and 2.5” drives, the same power connector can be used on both 3.5” and 2.5” form factor products. This allows simpler PC system designs, which leads to cost reduction.

Serial ATA 1.0, with its cable noise tolerance and serial transfer features, supports bandwidth of 1.5Gbit/s which provides 10% faster data transfer rate up to 150MB/s compared to ATA-133. The simplified data transfer protocol of Serial ATA minimizes time delay of command process.

The Hot-plug feature is necessary for HDD to be used in RAID set. Having extra HDDs in RAID set over RAID 5 is to restore data with new HDD and recover previous functions without stopping the system when error occurs. Serial ATA features hot-plug capability that enables the system to be restored without stopping its function. This feature allows the drive to be utilized in servers.

Although Cyclic Redundancy Checking capability exists in P-ATA, the Serial ATA has improved its capability to protect data, thus enhancing data reliability.

The 1st generation standard for Serial ATA 1.0 has been released. 2nd and 3rd generation standard for entry-level servers will be introduced in 2004 and 2007, respectively.

SAMSUNG, before producing the Motherboard backing the Serial ATA, tested its compatibility with ABIT and Promise Add On Card. SAMSUNG also tested compatibility and performance with most computers with Motherboard (Intel 875 chipset) backing the Serial ATA. The results of the tests suggested that there were no compatibility problems. With the introduction of Serial ATA chipset from Intel, the industry will rapidly adopt the new interface and Samsung is ready to provide the customers with high performance Serial ATA interface products.