IBM C2B 2.25 Brick On Sled carrier 128-pin HPC User Manual
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USER 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 SPECIFICATION ULTRASTAR X P (DFHC) SSA M O D E L S 1.12/2.25 GB - 1.0" H I G H
Termination
Bus termination of the - SYNC signals is internal to the drive. This signal has a 5.1K ohm pulled-up to
the + 5 volt supply. A maximum of 30 drives can have their - SYNC line daisy chained together. Vio-
lating this could damage the Master drive line driver on the - SYNC line
It is the using system's responsibility to provide the cable to connect the - SYNC line where needed, of
the synchronized drives.
Bus Characteristics
−
maximum Bus length = 6 meters
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2 micro-second negative active pulse (when sourced by drive)
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minimum of 1 micro-second negative active pulse when externally sourced
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0.8 volts = valid low input
−
2.2 volts = valid high input
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0.4 volts = low output
−
Vcc volts = High output
−
30 milli-amps = maximum output low level sink current
The driver used for these two signal lines is a Open Drain buffer.
Source filename=SYNC
IBM Corporation
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