Motorola MVME2603-1121A, Инструкция по установке и эксплуатации

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EIA-530 Connections
C-8
C
Interface Characteristics
In specifying parameters for serial binary data interchange between
DTE and DCE devices, the EIA-530 standard assumes the use of
balanced lines, except for the Remote Loopback, Local Loopback,
and Test Mode lines, which are single-ended. Balanced-line data
interchange is generally employed in preference to unbalanced-line
data interchange where any of the following conditions prevail:
❏
The interconnection cable is too long for effective unbalanced
operation.
❏
The interconnection cable is exposed to extraneous noise
sources that may cause an unwanted voltage in excess of
±
1V
measured differentially between the signal conductor and
circuit ground at the load end of the cable, with a 50
Ω
resistor
substituted for the transmitter.
❏
It is necessary to minimize interference with other signals.
❏
Inversion of signals may be required (e.g., plus polarity
MARK to minus polarity MARK may be achieved by
inverting the cable pair).
EIA-530 interface transmitter and receiver parameters applicable to
the MVME2603/2604 are listed in the following tables.
Table C-5. EIA-530 Interface Transmitter Characteristics
Parameter
Value
Unit
Minimum Maximum
Differential output voltage (absolute, with
100
Ω
load)
2.0
V
Open circuit differential voltage output
(absolute)
6.0 V
Output offset voltage (with 100
Ω
load) 2.0 V
Short circuit output current (for any voltage
between
−
7V and +7V)
±
180 mA
Power off output current (for any voltage
between
−
7V and +7V)
±
100
µ
A
Output transition time (with 100
Ω
, 15pF load) 15 ns