Constellation CS Serial ATA Product Manual, Rev. C
7
www.seagate.com
2.6
Seek time
Seek measurements are taken with nominal power at 25°C ambient temperature. All times are measured using drive
diagnostics. The specifications in the table below are defined as follows:
•
Track-to-track seek time is an average of all possible single-track seeks in both directions.
•
Average seek time is a true statistical random average of at least 5000 measurements of seeks between random tracks, less
overhead.
2.7
Start/stop times
2.8
Power specifications
The drive receives DC power (+5V or +12V) through a native SATA power connector. Refer to
Figure 6 on page 23
.
2.8.1
Power consumption
Power requirements for the drives are listed in
Table 2:
. Typical power measurements are based on an average of drives tested,
under nominal conditions, using 5.0V and 12.0V input voltage at 25°C ambient temperature.
• Spinup power
Spinup power is measured from the time of power-on to the time that the drive spindle reaches operating speed.
• Seek mode
During seek mode, the read/write actuator arm moves toward a specific position on the disc surface and does not execute a
read or write operation. Servo electronics are active. Seek mode power represents the worst-case power consumption, using
only random seeks with read or write latency time. This mode is not typical and is provided for worst-case information.
• Read/write power and current
Read/write power is measured with the heads on track, based on a 16-sector write followed by a 32-ms delay, then a 16-
sector read followed by a 32-ms delay.
• Operating power and current
Operating power is measured using 40 percent random seeks, 40 percent read/write mode (1 write for each 10 reads) and
20 percent drive idle mode.
• Idle mode power
Idle mode power is measured with the drive up to speed, with servo electronics active and with the heads in a random track
location.
• Standby mode
During Standby mode, the drive accepts commands, but the drive is not spinning, and the servo and read/write electronics
are in power-down mode..
Typical seek times (ms)
Read
Write
Track-to-track
0.5
0.8
Average
9.5
10.5
Average latency
4.16
Note
These drives are designed to consistently meet the seek times represented in this manual. Physical seeks,
regardless of mode (such as track-to-track and average), are expected to meet the noted values. However,
due to the manner in which these drives are formatted, benchmark tests that include command overhead or
measure logical seeks may produce results that vary from these specifications.
3TB models
2TB models
1TB models
Power-on to ready (sec)
15 (max)
10 (max)
7.0 (max)
Standby to ready (sec)
15 (max)
10 (max)
7.0 (max)
Ready to spindle stop (sec)
20 (max)
