Figure 2. Typical Power-On Sequence - Seagate ST251 Product Manual

1.9 DC POWER SPECIFICATIONS
FIGURE
1:
Typical
+ 12
VDC Start-Up Current Profile
Power may be applied or removed in any sequence without loss of
data or damage to the drive.
Typical seek currents are measured on a buffered one-third stroke
seek followed by two revolutions of non-seek time.
Maximum seek currents are measured on repetitive 3-track buffered
seeks with a one-half spindle rotation between each seek.
20
15
5 msec. max. H
10
SECONDS
- SEEK COMPLETE
-----------
....•
((
(
..
(-------
II II
1 _
_ READY 20
msec. max·H
______ ~_-i(( ((
II
I/~-----I
------
- TRACK 0
_.I( (~
'.1
.J
---
FIGURE
2:
Typical Power-On Sequence
(( ((
1_--)) ))'" -----------
DC ON
~12
sec. typo ~
ROTATIONAL SPEED
~r;
REGULATED ±O.5% (
.I
~ 10 sec. typo ~
fi(
~
j
(
\
( (
( (
13 Watts typo
11 Watts typo
0.7 Amps max. RMS
0.5 Amps typo RMS
±5% both seek and nonseek con-
ditions
1.4 Amps max. Peak
1.1 Amps max. RMS
0.9 Amps typo RMS
1.3 Amps max. RMS
1.0 Amps typo RMS
±5% both seek and nonseek con-
ditions
2.0 Amps
1.8 Amps max. Peak
1.1 Amps max. RMS
0.7 Amps typo RMS
+
5
VDC
Voltage Tolerance (inc. ripple):
+
12 VDC
Voltage Tolerance (inc. ripple):
Nonseeking Current:
Seeking Cu rrent:
Nonseeking Current:
POWER
Seeking:
Nonseeking:
Max. Current at Power-Up:
Seeking Current:
Typical seeking/nonseeking current and power specifications assume
nominal voltages applied, 25°C ambient temperature, sea level and
spindle rotating.
Maximum (3 sigma max.) seeking/nonseeking current specifications
assume 10° C ambient temperature, 5.25 VDC and 12.6 VDC applied,
sea level and spindle rotating.
14 25 sec. max. al
1-8
ST251 /251 R/277R Product Manual, Rev.A
ST251 /251 R/277R Product Manual, Rev.A
1-9