LSI53C040-160QFP LSI, LSI53C040-160QFP Datasheet - Page 26

• Manufacturer Part Number: LSI53C040-160QFP
• Manufacturer: LSI

Specifications of LSI53C040-160QFP

• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Supplier Unconfirmed

2.3.2 LVDlink™ Technology
2.3.3 Programmed I/O Transfers
2-8
To support greater device connectivity and a longer SCSI cable, the
LSI53C040 includes LVDlink technology, the LSI Logic implementation of
LVD SCSI. LVDlink transceivers provide the inherent reliability of
differential SCSI, and a long-term migration path for faster SCSI transfer
rates.
LVDlink technology is based on current drive; its low output current
reduces the power needed to drive the SCSI bus, so that the I/O drivers
can be integrated directly onto the chip. This reduces cost and
complexity compared to high-power differential designs. LVDlink lowers
the amplitude of noise reflections and allows higher transmission
frequencies.
The LSI Logic LVDlink transceivers operate in LVD and SE modes. The
LSI53C040 automatically detects which type of signal is connected,
based on voltage detected by the DIFFSENS pin.
The RBIAS+ and RBIAS signals are the bias resistors for LVD
operation. A resistor value of 9.76 k
illustrated in
Figure 2.4
3.3 V
Programmed I/O is the most primitive form of data transfer. The REQ/
and ACK/ handshake signals are individually monitored and asserted by
reading and writing the appropriate register bits. This type of transfer is
normally used when transferring small blocks of data such as command
blocks or message and status bytes.
I/O transfer.
Functional Description
9.76 k
Figure
LVD Resistor Value
RBIAS
RBIAS
2.4.
Figure 2.5
1%, is recommended, as
illustrates a programmed