Cheetah X15 36LP Product Manual, Rev. D
6.0
Physical/electrical specifications
This section provides information relating to the physical and electrical characteristics of the Cheetah X15
36LP drive.
6.1
AC power requirements
None.
6.2
DC power requirements
The voltage and current requirements for a single drive are shown in the following table. Values indicated apply
at the drive power connector. The table shows current values in Amperes.
Table 3:
DC power requirements
Voltage
Regulation
Average idle current DC
Maximum starting current
(peak DC) DC
(peak AC) AC
Delayed motor start (max) DC
Peak operating current
DC
Maximum DC
Maximum (peak) DC
[1]
Measured with average reading DC ammeter or equivalent sampling scope. Instantaneous current peaks
will exceed these values. Power supply at nominal voltage. N (number of drives tested) = 6, 35 Degrees C
ambient.
[2]
For +12 V, a –10% tolerance is permissible during initial start of spindle, and must return to ±5% before
15,000 rpm is reached. The ±5% must be maintained after the drive signifies that its power-up sequence
has been completed and that the drive is able to accept selection by the host initiator.
[3]
See +12 V current profile in Figure 2.
[4]
This condition occurs when the Motor Start Option is enabled and the drive has not yet received a Start
Motor command.
[5]
See Section 6.2.1 "Conducted Noise Immunity." Specified voltage tolerance is inclusive of ripple, noise,
and transient response.
[6]
Operating condition is defined as random 8 block reads at 282 I/Os per second (284 I/Os per second for
. Current and power specified at nominal voltages. Decreasing +5 volts by 5% increases
ST318452 models)
5 volt current by 3.2%. Decreasing +12 volt supply by 5% increases 12 volt current by 1.4% (2% for
.
ST318452 models)
[7]
During idle, the drive heads are relocated every 60 seconds to a random location within the band from
three-quarters to maximum track.
General Notes from Table 3:
1. Minimum current loading for each supply voltage is not less than 1.7% of the maximum operating current
shown.
2. The +5 and +12 volt supplies shall employ separate ground returns.
3. Where power is provided to multiple drives from a common supply, careful consideration for individual
drive power requirements should be noted. Where multiple units are powered on simultaneously, the peak
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.
ST336752 and ST336732
Notes
SE mode
+5 V
+12 V
[5]
±5%
±5%[2] ±5%
X [1][7] 0.78
0.68
[3]
0.83
1.73
3σ
[3]
1.16
3.33
3σ
[1][4] 0.68
0.03
3σ
X
[1][6]
0.81
0.98
[1]
0.85
1.23
3σ
1.25
2.25
3σ
ST318452 and ST318432
LVD mode
SE mode
+5 V
+12 V
+5 V
±5%[2] ±5%
0.83
0.68
0.78
0.92
1.73
0.87
1.22
3.33
1.21
0.73
0.03
0.69
0.89
0.98
0.79
0.93
1.23
0.84
1.55
2.25
1.18
21
LVD mode
+12 V
+5 V
+12 V
±5%[2] ±5%
±5%[2]
0.51
0.83
0.51
1.44
0.90
1.44
2.51
1.18
2.51
0.03
0.74
0.03
0.79
0.88
0.79
0.99
0.93
0.99
2.32
1.44
2.32