Here are the pinouts for both Serial ATA data cable and Serial ATA power supply cable. As mentioned before, Serial ATA uses two separated data channels, named A and B, using differential transmission, hence the + and – symbols below. On the wires marked with the minus signal, the data is an inverted copy of what is being transmitted on the corresponding wires with plus signal. Click here to learn how differential transmission works.

Serial ATA Data Connector

Pin	Function
1	Ground
2	A+
3	A-
4	Ground
5	B-
6	B+
7	Ground

Serial ATA Power Connector

Pin	Function
1	+3.3 V
2	+3.3 V
3	+3.3 V
4	Ground
5	Ground
6	Ground
7	+5 V
8	+5 V
9	+5 V
10	Ground
11	Reserved/Ground
12	Ground
13	+12 V
14	+12 V
15	+12 V