Seagate ST43400N/ND user manual Power requirements

12

Power requirements

The voltage and current requirements for a single drive at cylinder 0 are shown in Table 3.

Table 3. Single drive voltage and current requirements
	Current without Internal			Current with Internal
		Terminator			Terminator
		Seeking	Contin-		Seeking	Contin-
		and	uous		and	uous
Voltage	Idle	Reading	Reading	Idle	Reading	Reading
SCSI single-ended interface
+5 V	1.87 A	1.91 A	2.00 A	1.90 A	1.96 A	2.09 A
+12 V	1.57 A	1.92 A	1.56 A	1.57 A	1.90 A	1.56 A
Watts	28.19 W	32.59 W	28.72 W	28.34 W	32.60 W	29.17 W
SCSI differential interface
+5 V	2.32 A	2.63 A	2.75 A	2.45 A	2.77 A	2.85 A
+12 V	1.63 A	1.88 A	1.64 A	1.63 A	1.88 A	1.66 A
Watts	31.21 W	35.71 W	33.40 W	31.81 W	36.41 W	34.17 W

	Without Internal		With Internal
	Terminator		Terminator
Maximum Current Limits	+5 V	+12 V	+5 V	+12 V
SCSI single-ended interface
Maximum operating current*	2.06 A	3.09 A	2.37 A	3.04 A
Average idle current	1.84 A	1.92 A	1.96 A	1.92 A
Maximum starting current*	2.06 A	3.98 A	2.37 A	3.98 A
Maximum seek current*	1.89 A	2.12 A	2.16 A	3.19 A
SCSI differential interface
Maximum operating current*	2.98 A	2.88 A	3.48 A	3.17 A
Average idle current	2.11 A	1.85 A	2.45 A	1.63 A
Maximum starting current*	2.98 A	3.98 A	3.48 A	4.60 A
Maximum seek current*	2.31 A	2.13 A	3.48 A	3.17 A

*Instantaneous +12 V current peaks will exceed these values by up to 0.8 A.