IBM C2B 2.25 Brick On Sled carrier 128-pin HPC, SSA Example 4. Calculate the 12 volt peak current

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U S E R RESPONSIBLE F O R V E R I F Y I N G VERSION A N D COMPLETENESS

O E M F U N C T I O N A L S P E C I F I C A T I O N U L T R A S T A R X P ( D F H C ) SSA M O D E L S 1.12/2.25 G B - 1.0" H I G H

Example 4. Calculate the 12 volt peak current.

T o compute the sum of the 12 volt peak currents the following is done.

	mean
+ 1 2 V D C (idle avg)	0.28	amps
+ 1 2 V D C (seek peak)	1.2	amps
T O T A L	1.48	amps

Example 5. Calculate the mean plus 3 sigma 12 volt peak current.

T o 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
+ 1 2 V D C (idle avg)	0.02 amps
+ 1 2 V D C (seek peak)	0.02 amps

T O T A L 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.

Source filename=POWER

I B M Corporation

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Contents Form Factor Disk Drive Version BM Corporation Preface Source filename=STSSHEXT When Operating Limits ReliabilityContaminants Acoustic Levels Source filename=STSSHEXT General Features FeaturesInterface Controller Features DescriptionModels Reliability FeaturesGeneral SpecificationsSectors/logical block sct/lba User bytes/sector ub/sctUser bytes/logical block ub/lba Sectors/track sct/trkFor Each Notch Capacity EquationsFor Entire Drive 1 C1x Models Power Requirements by ModelInput Voltage + 5 Volts Supply + 1 2 Volts SupplyExample 1. Calculate the mean 12 volt average current Power Calculation ExamplesExample 3. Power Calculation Example 4. Calculate the 12 volt peak current Things to check when measuring 12 V supply currentVolt current during read/write operations C1x Models Typical 12 volt current C1x Models Typical 12 volt spin-up current C1x Models 2 C2x Models Power Calculation Examples Example 4. Calculate the 12 volt peak current Volt current during read/write operations C2x Models Typical 12 volt current C2x Models Typical 12 volt spin-up current C2x Models 3 C4x Models Power Calculation Examples Example 4. Calculate the 12 volt peak current Volt current during read/write operations C4x Models Typical 12 volt current C4x Models Typical 12 volt spin-up current C4x Models 4.2 DC/DC Converter Power supply methodsCxB Models Hot plug/unplug support Grounding Requirements of the Disk EnclosureM Corporation Event Nominal Maximum Bring-up Sequence and Stop TimesBring-up Sequence Times and Stop Time for C2x Models Source filename=PERFORM Environment Definition PerformanceWorkload Definition # of segments Ub/lba +Sequential Command Execution TimeRandom Basic Component DescriptionsData Transfer to/from Disk Data Transfer to/from SSA Link CommentsTheoretical Data Sector Transfer Rate Approximating Performance for Different EnvironmentsWhen Write Caching is Enabled When Read Caching is EnabledWhen Adaptive Caching is Enabled When Read-ahead is EnabledFor Queued Commands When No Seek is RequiredReordered Commands Back-To-Back CommandsTrack to Track Skew SkewCylinder to Cylinder Skew Idle Time Functions Servo Bias Measurements Servo Run Out MeasurementsPredictive Failure Analysis Channel CalibrationDisk Sweep Command Timeout LimitsSave Logs and Pointers M Corporation Mechanical Weight and DimensionsSmall Form Factor Models CxC ClearancesDimensions are in millimeters Location of Side Mounting Holes of C4C Models Source filename=MECHANIC Unitized Connector Locations Source filename=MECHANIC Carrier Models CxB Dimensions CxB Models M Corporation Handle Docking and Ejection System Auto-docking Assembly Side Rails Side Rail Positioning E D Locations front view CxB Models M Corporation Electrical Connector and Indicator LocationsElectrical Interface SSA Unitized ConnectorPin Carrier ConnectorRow SSA Link Cable SSA Link Electrical CharacteristicsOption Pins and Indicators Device Fault Pin/Indicator Option Port Pin Device Activity Pin/Indicator Option Port PinWrite Protect Option Port Pin Ground long Option Port PinEarly Power Off Warning or Power Fail Power Port Pin Front Jumper Connector12 12V Charge and 5V Charge Power Port pin 1 Programmable pin 1 Option Port PinSpindle Synchronization Over Sync Hard-wire M Corporation Source filename=RELIABLE Seek Error Rate Error DetectionPower On Hours Examples ReliabilityUseful Life Power on/off cyclesMaximum on/off cycles Product LifeMean Time Between Failure *MTBF Install Defect FreeSpql Shipped product quality level Sample Failure Rate ProjectionsConnector Insertion Cycles Periodic MaintenanceInstall Defect Free percentage Percent ESD ProtectionOperating Limits Temperature Measurement PointsP F E T Maximum ReliabilityVibration and Shock Temperature Measurement Points for all Models bottom viewOperating Vibration Drive Mounting GuidelinesOutput Vibration Limits V4S Nonoperating VibrationNonoperating Shock ContaminantsOperating Shock Acoustic Levels Upper Limit Sound Power Requirements Bels for C4x ModelsSource filename=STANDARD Electromagnetic Compatibility EMC SafetyStandards M Corporation Serial Storage Architecture S S a P H Transport Bibliography