Interface Cable; Se And Lvd Transmission Line Impedance Of Cable At Maximum Indicated; Attenuation Requiaments For Scsi Cable Media - Fujitsu MAN3184 SERIES Specifications

1.3.2

Interface cable

Use the twisted-pair interface cables satisfying the requirements of Tables 1.4 ,1.5.
Table 1.4 SE and LVD Transmission line impedance of cable at maximum indicated data transfer
Description
All
Note:
If SCSI loads attached to the cable media are separated by more than 1.0 m use the value of 78
Ohms.
Table 1. 5
Distance between
SCSI bus
terminators (meters)
0 to 9
0 to 12
>12 to 25
A twisted-pair cable must consist of pin n and pin n+1 (where "n" is an odd number) of the
interface connector. Use the SCSI bus cables having the same impedance characteristics to
minimize the signal reflection but keep the highest possible transmission characteristics.
If SCSI devices are connected to the terminals other than the interface cable ends, use the cable
branch at the SCSI connectors. No more SCSI cable can be connected to the last SCSI device
(which is connected to the SCSI bus) except when it is terminated with the terminator (see Figure
1.11).
The interface cable must have the stub length less than 0.1 meter for the single-ended SCSI cable.
Separate the stabs at least 0.3 meter from each other. (Keep the stab at least 30 cm away from a
SCSI device.)
rate
Local SE transmission line
impedance
Minimum
84 Ohms (78
Ohms) (Note)

Attenuation Requiaments for SCSI cable media

Distances are consistent with these
minimum size conductors when used
with high quality dielectrics
2
0.0324 mm (32 AWG) solid/
2
0.05092 mm (30 AWG) stranded
2
0.05092 mm (30 AWG) solid/
2
0.08042 mm (28 AWG) stranded
2
0.05092 mm (30 AWG) solid/
2
0.08042 mm (28 AWG) stranded
C141-E123-01EN
Local differential
transmission line impedance
Maximum Minimum
96 Ohms 110 Ohms
multiple loads allowed
multiple loads allowed
point to point only
Maximum
135 Ohms
Notes
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