Seagate ST3400820SCE ユーザーズマニュアル
16
DB35.3 Series Serial ATA Product Manual, Rev. D
Figure 2. Typical 12V startup and operation current profile
2.8.2
Conducted noise
Input noise ripple is measured at the host system power supply across an equivalent 80-ohm resistive load on
the +12 volt line or an equivalent 15-ohm resistive load on the +5 volt line.
the +12 volt line or an equivalent 15-ohm resistive load on the +5 volt line.
• Using 12-volt power, the drive is expected to operate with a maximum of 120 mV peak-to-peak square-wave
injected noise at up to 10 MHz.
• Using 5-volt power, the drive is expected to operate with a maximum of
100 mV peak-to-peak square-wave
injected noise at up to 10 MHz.
Note. Equivalent resistance is calculated by dividing the nominal voltage by the typical RMS read/write
current.
2.8.3
Voltage tolerance
Voltage tolerance (including noise):
5V ± 5%
12V ± 10%
2.8.4
Power-management modes
The drive provides programmable power management to provide greater energy efficiency. In most systems,
you can control power management through the system setup program. The drive features the following
power-management modes:
you can control power management through the system setup program. The drive features the following
power-management modes:
• Active mode
The drive is in Active mode during the read/write and seek operations.
Power modes
Heads
Spindle
Buffer
Active
Tracking
Rotating
Enabled
Idle
Tracking
Rotating
Enabled
Standby
Parked Stopped
Enabled
Sleep
Parked
Stopped
Disabled