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Serial Interconnections

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 (for example, 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 

 and 

.

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