Seagate ST98823AS Momentus 5400.2 SATA Product Manual - Page 16

2.9.3 Conducted noise Input noise ripple is measured at the host system power supply across an equivalent 15-ohm resistive load on the +5 volt line. 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. 2.9.4 Voltage tolerance Voltage tolerance (including noise): 5V ± 5% 2.9.5 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: Table 4: Power management modes Power modes Active (operating) Idle, performance Idle, active Idle, low power Standby Sleep Heads Tracking Tracking Floating Parked Parked Parked Spindle Rotating Rotating Rotating Rotating Stopped Stopped Buffer Full power Self refresh-low power Self refresh-low power Self refresh-low power Self refresh-low power Self refresh-low power • Active mode The drive is in Active mode during the read/write and seek operations. • Idle mode The buffer remains enabled, and the drive accepts all commands and returns to Active mode any time disc access is necessary. • Standby mode The drive enters Standby mode when the host sends a Standby Immediate command. If the host has set the standby timer, the drive can also enter Standby mode automatically after the drive has been inactive for a specifiable length of time. The standby timer delay is established using a Standby or Idle command. In Standby mode, the drive buffer is in Self Refresh Low Power mode, the heads are parked and the spindle is at rest. The drive accepts all commands and returns to Active mode any time disc access is necessary. • Sleep mode The drive enters Sleep mode after receiving a Sleep command from the host. In Sleep mode, the drive buffer is in Self Refresh Low Power mode, the heads are parked and the spindle is at rest. The drive leaves Sleep mode after it receives a Hard Reset or Soft Reset from the host. After receiving a reset, the drive exits Sleep mode and enters Standby mode with all current translation parameters intact. 10 Momentus 5400.2 SATA Product Manual, Rev. C