Seagate ST3300655LW, ST3146855LC manual Conducted noise immunity, Power sequencing, Current profile

starting current must be available to each device.

4.Parameters, other than spindle start, are measured after a 10-minute warm up.

5.No terminator power.

7.2.1Conducted noise immunity

Noise is specified as a periodic and random distribution of frequencies covering a band from DC to 10 MHz. Maximum allowed noise values given below are peak-to-peak measurements and apply at the drive power connector.

+5 V	=	250 mV pp from 0 to 100 kHz to 20 MHz.
+12 V	=	800 mV pp from 100 Hz to 8 KHz.
		450 mV pp from 8 KHz to 20 KHz.
		250 mV pp from 20 KHz to 5 MHz.

7.2.2Power sequencing

The drive does not require power sequencing. The drive protects against inadvertent writing during power-up and down. Daisy-chain operation requires that power be supplied to the SCSI bus terminator to ensure proper termination of the peripheral I/O cables. To automatically delay motor start based on the target ID (SCSI ID) enable the Delay Motor Start option and disable the Enable Motor Start option on the J6 connector on LW mod- els or on the backplane for LC models. See Section 9.1 for pin selection information. To delay the motor until the drive receives a Start Unit command, enable the Enable Remote Motor Start option on the J6 connector on LW models or on the backplane for LC models.

7.2.3Current profile

Figures 1 and 2 show +5V and +12V sample current profiles for the ST3300655LC model.

All times and currents are typical. See Table 3 for maximum current requirements.

24 Cheetah 15K.5 SCSI Product Manual, Rev. J