Technical information

CHAPTER 3
Devices and Ports
36 Hard Disk Drive
Hard Disk Connector 3
The internal hard disk has a 48-pin connector that carries both the ATA signals
and the power for the drive. The connector has the dimensions of a 50-pin
connector, but with one row of pins removed, as shown in Figure 3-3. The
remaining pins are in two groups: pins 1–44, which carry the signals and power,
and pins 46–48, which are reserved. Pin 20 has been removed, and pin 1 is
located nearest the gap, rather than at the end of the connector.
Figure 3-3 Hard disk connector and location
Signal Assignments 3
Table 3-3 shows the signal assignments on the 44-pin portion of the hard disk
connector. A slash (/) at the beginning of a signal name indicates an active-low
signal.
3.99
[0.157]
10.14 ± 0.375
[0.399 ± 0.014]
Key: vacant
position at pin 20
Vacant row in
50-pin connector
Pin 1
Center line of pin 44
10.24
[0.403]
14.00
[0.551]
12.70 maximum
[0.500 maximum]