Serial ATA

Serial ATA is an enhancement to the ATA standard for for connecting storage to PC’s.

All versions of ATA up until ATA-7 in 2004 utilized parallel transfer of data from the motherboard to the drive controller built onto the disk.

The ATA-7 specification introduced Serial ATA.

Serial ATA Standards

The original Serial ATA standard offered miniminal improvement over the existing 133MBps bandwidth of the existing Parallel ATA standard.

Serial ATA standards are constantly evolving to meet higher bandwidth requirements.

Serial ATA Type	Bandwith	Bus Speed	Signal Rate
SATA-150	150MBps	1500MHz	1.5Gbps
SATA-300	300MBps	3000MHz	3.0Gbps
SATA-600	600MBps	6000MHz	6.0Gbps

Serial ATA Data Cables

Higher bandwidth requirements were pushing requirements for shorter Parallel ATA data cables. Serial ATA reversed this trend by allowing data cables up to 1 meter in length.

eSATA (External SATA) allows the use of shielded cables up to 2 meters in length for external drives.

Serial ATA Power Cables

The serial ATA power cable uses a 15-pin wafer connector to provide 3.3, 5, or 12 volts to ATA devices.