IBM C1B 1.12 Brick On Sled Carrier 128-pin HPC User manual

OEM FUNCTIONAL SPECIFICATION
ULTRASTAR XP (DFHC) SSA MODELS
1.12/2.25 GB - 1.0" HIGH
4.51 GB - 1.6" HIGH
3.5 FORM FACTOR DISK DRIVE
VERSION 5.0
August 15, 1995
Publication number 3304
IBM Corporation
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Preface
This document details the product hardware specification for the Ultrastar XP SSA family of Direct Access
Storage Devices. The capacity model offerings are 1.12, 2.25, and 4.51 GBytes (see 2.1.1, “Capacity
Equations” on page 13 for exact capacities based on model and block size). The form factor offerings are
'Brick On Sled' carrier and 3.5-inch small form factor (refer to 4.1.1, “Weight and Dimensions” on page 51
for exact dimensions).
This document, in conjunction with the Ultrastar XP (DFHC) SSA Models Interface Specification, make
up the Functional Specification for the Ultrastar XP SSA (DFHC) product.
The product description and other data found in this document represent IBM's design objectives and is
provided for information and comparative purposes. Actual results may vary based on a variety of factors
and the information herein is subject to change. THIS PRODUCT DATA DOES NOT CONSTITUTE A
WARRANTY, EXPRESS OR IMPLIED. Questions regarding IBM's warranty terms or the methodology
used to derive the data should be referred to your IBM customer representative.
Note: Not all models described in this document are in plan. Contact your IBM customer representative
for actual product plans.
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Contents
1.0 Description .................................................... 9
1.1 Features ...................................................... 9
1.1.1 General Features .............................................. 9
1.1.2 Performance Summary .......................................... 9
1.1.3 Interface Controller Features ....................................... 9
1.1.4 Reliability Features ........................................... 10
1.2 Models ..................................................... 10
2.0 Specifications .................................................. 11
2.1 General ..................................................... 11
2.1.1 Capacity Equations ........................................... 13
2.2 Power Requirements by Model ....................................... 15
2.2.1 C1x Models ................................................ 15
2.2.2 C2x Models ................................................ 21
2.2.3 C4x Models ................................................ 27
2.2.4 CxB Models ............................................... 33
2.2.5 Power Supply Ripple .......................................... 34
2.2.6 Grounding Requirements of the Disk Enclosure ........................... 34
2.2.7 Hot plug/unplug support ........................................ 34
2.2.8 Bring-up Sequence (and Stop) Times ................................. 36
3.0 Performance .................................................. 39
3.1 Environment Definition ........................................... 39
3.2 Workload Definition ............................................. 39
3.2.1 Sequential ................................................. 40
3.2.2 Random .................................................. 40
3.3 Command Execution Time ......................................... 40
3.3.1 Basic Component Descriptions ..................................... 40
3.3.2 Comments ................................................ 42
3.4 Approximating Performance for Different Environments ......................... 43
3.4.1 For Different Transfer Sizes ....................................... 44
3.4.2 When Read Caching is Enabled .................................... 44
3.4.3 When Write Caching is Enabled .................................... 44
3.4.4 When Adaptive Caching is Enabled .................................. 44
3.4.5 When Read-ahead is Enabled ...................................... 44
3.4.6 When No Seek is Required ....................................... 45
3.4.7 For Queued Commands ......................................... 45
3.4.8 Out of Order Transfers ......................................... 45
3.5 Skew ...................................................... 46
3.5.1 Cylinder to Cylinder Skew ....................................... 46
3.5.2 Track to Track Skew .......................................... 46
3.6 Idle Time Functions ............................................. 47
3.6.1 Servo Run Out Measurements ..................................... 48
3.6.2 Servo Bias Measurements ........................................ 48
3.6.3 Predictive Failure Analysis ....................................... 48
3.6.4 Channel Calibration ........................................... 48
3.6.5 Save Logs and Pointers ......................................... 49
3.6.6 Disk Sweep ................................................ 49
3.6.7 Summary ................................................. 49
3.7 Command Timeout Limits .......................................... 49
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4.0 Mechanical ................................................... 51
4.1 Small Form Factor Models (CxC) ..................................... 51
4.1.1 Weight and Dimensions ......................................... 51
4.1.2 Clearances ................................................. 51
4.1.3 Mounting ................................................. 51
4.1.4 Unitized Connector Locations ..................................... 55
4.2 Carrier Models (CxB) ............................................. 57
4.2.1 Weight and Dimensions ......................................... 57
4.2.2 Clearances ................................................. 57
4.2.3 Mounting ................................................. 57
4.2.4 Auto-docking Assembly Side Rails .................................. 60
4.2.5 Electrical Connector and Indicator Locations ............................ 62
5.0 Electrical Interface .............................................. 63
5.1 SSA Unitized Connector ........................................... 63
5.2 Carrier Connector ............................................... 64
5.3 SSA Link Cable ................................................ 66
5.4 SSA Link Electrical Characteristics ..................................... 66
5.5 Option Pins and Indicators .......................................... 66
5.5.1 - Manufacturing Test Mode (Option Port Pin 1) .......................... 66
5.5.2 - Auto Start Pin (Option Port Pin 2) ................................. 66
5.5.3 - Sync Pin (Option Port Pin 3) ..................................... 66
5.5.4 - Write Protect (Option Port Pin 4) .................................. 67
5.5.5 - Ground long (Option Port Pin 5) .................................. 67
5.5.6 - Device Activity Pin/Indicator (Option Port Pin 6) ......................... 67
5.5.7 + 5V (Option Port Pin 7) ....................................... 67
5.5.8 - Device Fault Pin/Indicator (Option Port Pin 8) .......................... 67
5.5.9 Programmable pin 1 (Option Port Pin 9) ............................... 68
5.5.10 Programmable pin 2 (Option Port Pin 10) ............................. 68
5.5.11 - Early Power Off Warning or Power Fail (Power Port Pin 11) ................. 68
5.5.12 12V Charge and 5V Charge (Power Port pin 1 and 2) ....................... 68
5.6 Front Jumper Connector ........................................... 68
5.7 Spindle Synchronization ........................................... 69
5.7.1 Synchronization overview ........................................ 69
5.7.2 Synchronization Mode ......................................... 69
5.7.3 Synchronization time .......................................... 69
5.7.4 Synchronization with Offset ...................................... 69
5.7.5 Synchronization Route ......................................... 69
6.0 Reliability .................................................... 73
6.1 Error Detection ................................................ 73
6.2 Data Reliability ................................................ 73
6.3 Seek Error Rate ................................................ 73
6.4 Power On Hours Examples: ........................................ 73
6.5 Power on/off cycles .............................................. 74
6.6 Useful Life ................................................... 74
6.7 *Mean Time Between Failure (*MTBF) .................................. 75
6.7.1 Sample Failure Rate Projections .................................... 75
6.8 SPQL (Shipped product quality level) ................................... 75
6.9 Install Defect Free ............................................... 75
6.10 Periodic Maintenance ............................................ 76
6.11 ESD Protection ............................................... 76
6.12 Connector Insertion Cycles ......................................... 76
7.0 Operating Limits ............................................... 77
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7.1 Environmental ................................................. 77
7.1.1 Temperature Measurement Points ................................... 77
7.2 Vibration and Shock ............................................. 79
7.2.1 Drive Mounting Guidelines ....................................... 80
7.2.2 Output Vibration Limits ........................................ 80
7.2.3 Operating Vibration ........................................... 80
7.2.4 Operating Shock ............................................. 82
7.2.5 Nonoperating Shock ........................................... 82
7.3 Contaminants ................................................. 82
7.4 Acoustic Levels ................................................ 83
8.0 Standards .................................................... 85
8.1 Safety ...................................................... 85
8.2 Electromagnetic Compatibility (EMC) ................................... 85
Bibliography ..................................................... 87
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1.0 Description
1.1 Features
1.1.1 General Features
1.12/2.25/4.51 gigabytes formatted capacity (512 bytes/sector)
Serial Storage Architecture (SSA) attachment (dual port)
Brick On Sled carrier and 3.5" small form factor models
Rotary voice coil motor actuator
Closed-loop digital actuator servo (embedded sector servo)
Magnetoresistive (MR) heads
(0,8,6,infinity) 8/9 rate encoding
Partial Response Maximum Likelihood (PRML) data channel with digital filter
All mounting orientations supported
Jumperable auto spindle motor start
Jumperable write protection
Spindle synchronization
Two LED drivers
Bezel (optional)
1.1.2 Performance Summary
Average read seek time (1.12 GB): 6.9 milliseconds
Average read seek time (2.25 GB): 7.5 milliseconds
Average read seek time (4.51GB): 8.0 milliseconds
Average Latency: 4.17 milliseconds
Split read/write control
Media data transfer rate: 9.59 to 12.58 MegaBytes/second (10 bands)
SSA data transfer rate: 20 Megabytes/second
1.1.3 Interface Controller Features
Multiple initiator support
Supports blocksizes from 256 to 5952 bytes
512K byte, multi-segmented, dual port data buffer
Read-ahead caching
Adaptive caching algorithms
Write Cache supported (write back & write thru)
Tagged command queuing
Command reordering
Back-to-back writes (merged writes)
Split reads and writes
Nearly contiguous read/write
Link error recovery procedure exit
Disable registration
Duplicate tags
Two byte ULP message codes
SCSI response
Move data transfer messages
Multiple ULP's
Automatic retry and data correction on read errors
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OEM FUNCTIONAL SPECIFICATION ULTRASTAR XP (DFHC) SSA MODELS 1.12/2.25 GB - 1.0" HIGH
Automatic sector reallocation
In-line alternate sector assignment for high-performance
Improved technique for down-loadable SSA firmware
1.1.4 Reliability Features
Self-diagnostics on power up
Dedicated head landing zone
Automatic actuator latch
Embedded Sector Servo for improving on-track positioning capability
Buffer memory parity
Longitudinal Redundancy Check (LRC) on Customer Data
ECC on the fly
Error logging and analysis
Data Recovery Procedures (DRP)
Predictive Failure Analysis (PFA &tm)
No preventative maintenance required
Two Field Replaceable Units (FRU's): Electronics Card and Head Disk Assembly (HDA)
Probability of not recovering data: 10 in 1015 bits read
1.2 Models
The Ultrastar XP SSA disk drive is available in various models as shown below.
The Ultrastar XP SSA data storage capacities vary as a function of model and user block size. The
emerging industry trend is capacity points in multiples of 1.08GB (i.e. 1.08/2.16/4.32) at a block size of 512
bytes. Future IBM products will plan to provide capacities that are consistent with this trend. Users that
choose to make full use of the Ultrastar XP SSA drive capacity above the standard capacity points may not
find equivalent capacity breakpoints in future products.
Model # Capacity GB (@512 Byte) Form Factor Connector Type
C1B 1.12 Brick On Sled Carrier 128-pin HPC
C1C 1.12 3.5-inch Small FF 38-pin Unitized
C2B 2.25 Brick On Sled carrier 128-pin HPC
C2C 2.25 3.5-inch Small FF 38-pin Unitized
C4B 4.51 Brick On Sled carrier 128-pin HPC
C4C 4.51 3.5-inch Small FF 38-pin Unitized
Note: CxB models (C1B, C2B, and C4B) include a DC/DC converter, activity and check indicators.
Note: Please refer to section 2.1.1, “Capacity Equations” on page 13 for exact capacities based on user block size.
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2.0 Specifications
All specifications are nominal values unless otherwise noted.
The Ultrastar XP SSA data storage capacities vary as a function of model and user block size. The
emerging Industry trend is capacity points in 1.08GB (i.e. 1.08/2.16/4.32) at a block size of 512 bytes. This
and future products will always plan to provide capacities that are consistent with this trend. Users that
choose to make full use of the Ultrastar XP SSA drive capacity above the standard capacity points may not
find equivalent capacity breakpoints in future products.
2.1 General
Note: The recording band located nearest the disk outer diameter (OD) is referred to as 'Notch #1'. While
the recording band located nearest the inner diameter (ID) is called 'Notch #10'. 'Average' values are
weighted with respect to the number of LBAs per notch when the drive is formatted with 512 byte blocks.
Data transfer rates Notch #1 Notch #10 Average
Buffer to/from media 12.58 9.59 12.07 MB/s (instantaneous)
Host to/from buffer up to 20.0 MB/s (synchronous) (sustained)
Data Buffer Size (bytes) 512 K (See 3.0, “Performance” on page 39 for user data capacity.)
Rotational speed (RPM) 7202.7
Average latency (milliseconds) 4.17
Track Density (TPI) 4352
Minimum Maximum
Recording density (BPI) 96,567 124,970
Areal density (Megabits/square inch) 420.3 543.9
(model numbers - > ) C4x C2x C1x
Disks 842
User Data Heads (trk/cyl) 16 8 4
Seek times (in milliseconds)
Single cylinder (Read) 0.5 0.5 0.5
(Write) 2.0 2.0 2.0
Average (weighted) (Read) 8.0 7.5 6.9
(Write) 9.5 9.0 8.5
Full stroke (Read) 16.5 15.0 14.0
(Write) 18.0 16.5 15.5
Note: Times are typical for a drive population under nominal voltages
and casting temperature of 25˚C. Weighted seeks are seeks to the cylin-
ders of random logical block addresses (LBAs).
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OEM FUNCTIONAL SPECIFICATION ULTRASTAR XP (DFHC) SSA MODELS 1.12/2.25 GB - 1.0" HIGH
Total Cylinders (tcyl) All models C4x Models C2x Models C1x Models
& User Cylinders (ucyl) tcyl ucyl ucyl ucyl
Notch #1 1893 1879 1877 1872
Notch #2 956 955 955 955
Notch #3 49 48 48 48
Notch #4 310 309 309 309
Notch #5 349 348 348 348
Notch #6 116 115 115 115
Notch #7 214 213 213 213
Notch #8 190 189 189 189
Notch #9 131 130 130 130
Notch #10 208 206 206 206
Sum of all Notches 4416 4392 4390 4385
Spares Sectors/cylinder (spr/cyl) C4x Models C2x Models C1x Models
Notch #1 40 20 10
Notch #2 40 20 10
Notch #3 38 19 10
Notch #4 37 19 9
Notch #5 36 18 9
Notch #6 34 17 9
Notch #7 33 17 8
Notch #8 32 16 8
Notch #9 31 16 8
Notch #10 30 15 7
Last cylinder extra spares (lcspr) 60 30 14
User bytes/sector (ub/sct) 256 - 744 (even number of bytes only)
Sectors/logical block (sct/lba) 1-8
The lowest sct/lba that satisfies the following rules is used...
1. Block Length is evenly divisible by a number 2-8.
2. Quotient of previous equation is evenly divisible by 2.
3. Quotient must be ≥256 and ≤744.
User bytes/logical block (ub/lba) 256 - 5952 (See rules for determining sct/lba above for determining sup-
ported ub/lba values.)
Sectors/track (sct/trk) (See Table 1 on page 13 or contact an IBM Customer Representative
for other block lengths.)
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Table 1. Gross sectors per track for several block lengths
Table 2. User capacity for several block lengths
2.1.1 Capacity Equations
2.1.1.1 For Each Notch
The next group of equations must be calculated separately for each notch.
user bytes/sector (ub/sct) = ub/lba
sct/lba
user sectors/cyl (us/cyl) = (sct/trk)(trk/cyl) - spr/cyl
spares/notch (spr/nch) = (spr/cyl)(ucyl)
Note: Add lcspr to the equation above for the notch closest to the inner diameter (#10).
user sectors/notch (us/nch) = (us/cyl)(ucyl)
Note: Subtract lcspr from the equation above for the notch closest to the inner diameter (#10).
Notch #
User bytes /
logical block 1 2 3 4 5 6 7 8 9 10
256 216 216 216 202 195 180 180 180 180 162
512 135 135 130 126 120 115 112 108 105 100
520 128 128 128 123 115 112 108 105 102 99
522 128 128 128 122 115 112 108 105 102 90
524 128 128 128 120 115 112 108 105 102 90
528 128 128 126 120 112 112 108 105 101 90
600 115 115 115 110 102 101 97 90 90 90
688 102 102 102 98 90 90 90 90 81 78
744 96 96 96 90 90 90 81 78 77 73
C4x Models C2x Models C1x Models
User bytes /
logical block formatted capacity
(bytes)
logical
blocks /
drive
formatted
capacity
(bytes)
logical
blocks /
drive
formatted
capacity
(bytes)
logical
blocks /
drive
256 3,654,540,800 14,275,550 1,826,312,448 7,134,033 912,135,680 3,563,030
512 4,512,701,440 8,813,870 2,255,098,368 4,404,489 1,126,337,536 2,199,878
520 4,375,536,880 8,414,494 2,186,554,760 4,204,913 1,092,119,600 2,100,230
522 4,374,300,492 8,379,886 2,185,931,898 4,187,609 1,091,803,716 2,091,578
524 4,385,878,952 8,369,998 2,191,716,460 4,182,665 1,094,691,544 2,089,106
528 4,408,629,984 8,349,678 2,203,082,640 4,172,505 1,100,365,728 2,084,026
600 4,512,402,000 7,520,670 2,254,925,400 3,758,209 1,126,282,800 1,877,138
688 4,604,578,976 6,692,702 2,300,969,904 3,344,433 1,149,310,880 1,670,510
744 4,675,830,192 6,284,718 2,336,559,528 3,140,537 1,167,099,408 1,568,682
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2.1.1.2 For Entire Drive
spares/drive (spr/drv) = ∑
10
notch = 1
spr/nch
user sectors/drive (us/drv) = ∑
10
notch = 1
us/nch
logical blocks/drive (lba/drv) = INT[us/drv
sct/lba ]
user capacity (fcap) = (lba/drv)(ub/lba)
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2.2 Power Requirements by Model
2.2.1 C1x Models
The following voltage specifications apply at the drive power connector. There is no special power on/off
sequencing required. The extra power needed for Brick On Sled models and the +38V power option are
described in 2.2.4, “CxB Models” on page 33.
Input Voltage
+ 5 Volts Supply 5V (± 5% during run and spin-up)
+12 Volts Supply 12V (± 5% during run) (+5% / -7% during spin-up)
The following current values are the combination measured values of SCSI models and SSA Cx4 model. The
differences between SCSI and SSA is +5V currents. Because of different interface electronics and speed, SSA
electronics card requires more +5V current than SCSI. Read/Write Base Line is 290 ma higher. Idle
Average is 500 ma higher. (290ma and 500ma differences were found by measuring SSA Cx4 model). SSA
+5V current numbers are derived from SCSI +5V current numbers by adding 290ma and 500ma accord-
ingly.
Population Population
Power Supply Current Notes Mean Stand. Dev.
+5VDC (power-up) Minimum voltage slew rate = 4.5 V/sec
+5VDC (idle avg) 1.23 Amps 0.02 Amps
+5VDC (R/W baseline) 1.25 Amps10.05 Amps
+5VDC (R/W pulse) Base-to-peak .36 Amps 0.06 Amps
+12VDC (power-up) Minimum voltage slew rate = 7.4 V/sec
+12VDC (idle avg) 0.28 Amps 0.02 Amps
+12VDC (seek avg) 1 op/sec 0.0027 Amps 0.002 Amps
+12VDC (seek peak) 1.20 Amps20.02 Amps
+12VDC (spin-up) 3.0 sec max 1.5 Amps30.1 Amps
Drive power
Avg idle power 9.51 Watts .35 Watts
Avg R/W power 30 ops/sec 10.58 Watts .35 Watts
1See Figure 1 on page 18 for a plot of how the read/write baseline and read/write pulse sum together.
2The idle average and seek peek should be added together to determine the total 12 volt peak current. See Figure 2
on page 19 for a typical buildup of these currents. Refer to examples on the following page to see how to combine
these values.
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2.2.1.1 Power Calculation Examples
Note: The following formulas assume all system ops as a 1 block read or write transfer from a random
cylinder while at nominal voltage condition.
Example 1. Calculate the mean 12 volt average current.
If we assume a case of 30 operations/second then to compute the sum of the 12 volt mean currents the
following is done.
mean
+12VDC (idle average) 0.28 amps
+12VDC (seek average) 0.027 * 30 = 0.081 amps
TOTAL 0.361 amps
Example 2. Calculate the mean plus 3 sigma 12 volt average current.
To compute the sum of the 12 volt mean current's 1 sigma value assume all the distributions are normal.
Therefore the square root of the sum of the squares calculation applies. Assume a case of 30
operations/second.
sigma
+12VDC (idle average) 0.02 amps
+12VDC (seek average) sqrt(30*((0.0002)**2))= 0.001 amps
TOTAL sqrt((0.02)**2+(.001)**2))=0.02 amps
So the mean plus 3 sigma mean current is 0.361 + 3*0.02 = 0.42 amps
Example 3. Power Calculation.
Nominal idle drive power = (1.23 Amps * 5 Volts) + (0.28 Amps * 12 Volts) = 9.51 Watts
Nominal R/W drive power at 30 ops/sec = (1.25 Amps * 5 Volts) + (0.361 Amps * 12 Volts) = 10.58
Watts
Mean plus 3 sigma drive power for 30 random R/W operations/second. Assume that the 5 volt and 12 volt
distributions are independent therefore the square root of the sum of the squares applies.
+5VDC (1 sigma power) 0.05 * 5 = 0.25 watts
+12VDC (1 sigma power) 0.02 * 12 = 0.24 watts
Total (1 sigma power) sqrt((0.25)**2+(0.24)**2) = 0.347 watts
Total power 9.13 + 3 * 0.347 = 10.2 watts
3The current at start is the total 12 volt current required (ie. the motor start current, module current and voice coil
retract current). See Figure 3 on page 20 for typical 12 volt current during spindle motor start.
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Example 4. Calculate the 12 volt peak current.
To compute the sum of the 12 volt peak currents the following is done.
mean
+12VDC (idle avg) 0.28 amps
+12VDC (seek peak) 1.2 amps
TOTAL 1.48 amps
Example 5. Calculate the mean plus 3 sigma 12 volt peak current.
To compute the sum of the 12 volt peak current's 1 sigma value assume all distributions are normal. There-
fore the square root of the sum of the squares calculation applies.
sigma
+12VDC (idle avg) 0.02 amps
+12VDC (seek peak) 0.02 amps
TOTAL sqrt((0.02)**2+(0.02)**2)=0.028 amps
So the mean plus 3 sigma peak current is 1.48 + 3*0.028 = 1.56 amps
Things to check when measuring 12 V supply current:
Null the current probe frequently. Be sure to let it warm up.
Adjust the power supply to 12.00 V at the drive terminals.
Use a proper window width, covering an integral number of spindle revolutions.
Measure values at 25 degree C casting temperature.
Get a reliable trigger for Seek Peak readings.
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Figure 1. 5 volt current during read/write operations —C1x Models
1. Read/write baseline voltage.
2. Read/write pulse. The width of the pulse is proportional to the number of consecutive blocks read or
written. The 5 volt supply must be able to provide the required current during this event.
Source filename=POWERIBM CorporationPage 18 of 87

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OEM FUNCTIONAL SPECIFICATION ULTRASTAR XP (DFHC) SSA MODELS 1.12/2.25 GB - 1.0" HIGH
Figure 2. Typical 12 volt current —C1x Models
1. Maximum slew rate is 7 amps/millisecond.
2. Maximum slew rate is 100 amps/millisecond.
3. Maximum slew rate is 7 amps/millisecond.
4. Maximum slew rate is 3 amps/millisecond.
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OEM FUNCTIONAL SPECIFICATION ULTRASTAR XP (DFHC) SSA MODELS 1.12/2.25 GB - 1.0" HIGH
Figure 3. Typical 12 volt spin-up current —C1x Models
1. Maximum slew rate is 20 amps/millisecond.
2. Current drops off as motor comes up to speed.
Source filename=POWERIBM CorporationPage 20 of 87