Picture Shown is a LVD-3.
What is LVD?
Flexibility, speed and much greater flexibility in cable lengths are the best reasons to
use Ultra2/Ultra160 LVD SCSI controllers. Ultra2/Ultra160 LVD SCSI is
Low Voltage Differential not to be confused with regular older versions of differential
properly known as High Voltage Differential or HVD. Differential in general uses two
noise canceling lines per signal to give you the ability to run longer cables at higher
speeds. Ultra2/Ultra160 SCSI can reach speeds of 80MBps/160MBps as upposed to the 40MBs
for Ultra wide SCSI.
- The terms LVD
and Ultra2 SCSI are used interchangeably.
- It is a subset
of the SCSI-3 standard.
- It provides
SCSI bus data rates of 80 Mbytes/sec.
- It provides
differential data integrity
- It extends
the SCSI bus cable lengths to 25 meters (12 meters with 16
devices)
- LVD was defined
in the original SCSI standards.
The increased
bandwidth of 80 Mbytes means optimal performance where rapid response
is required and random access and large queues are the norm. When
using applications such as CAD and CAM, digital video and any RAID
environment, the increased bandwidth is immediately noticeable as
information is moved quickly and effortlessly.
The lower voltage
requirements of LVD allow for the integration of the differential
drivers and receivers into the drive's onboard SCSI controller. The
older Ultra HVD design requires separate and costly high-voltage components.
LVD is fully compatible
with the existing single-ended SCSI base. A unique circuit determines
the type of SCSI bus the device is being used on, LVD or single-ended,
and configures the drive operation to the appropriate bus capability.
LVD devices will
work on SCSI-1and SCSI-2 bus segments. Older SCSI-1 and SCSI-2 single-ended
devices will work on an LVD bus.
When
using SCSI devices of different vintage on the same SCSI bus, all
peripherals on that bus will respond to the earliest version SCSI
specification.
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