PM6341 E1XC
DATA SHEET
PMC-910419
ISSUE 8
E1 FRAMER/TRANSCEIVER
Table 11
- RSLC Performance Limits
Signal
Type
Squelch
level
between
RAS – REF
Min. peak
ampl. on the on the primary
primary
Max. peak ampl. Recommended
signal gain
DSX-1A 105 mV
G.703
1.1
3.3
0.40 V/V
140 mV
140 mV
1.35 V
1.07 V
3.96 V
3.10 V
0.50 V/V
0.63 V/V
120Ω
75Ω
ITU-T Recommendation G.703 states the pulse height at the output port must
be 3.0V ± 10% for 120Ω twisted pair and 2.37V ± 10% for 75Ω coax with an
allowed overshoot of 20% above nominal. The maximum peak amplitude of
the primary assumes no transmission line losses and a maximum overshoot.
The minimum peak amplitude of the primary assumes a minimum output level
at the output port with 6 dB of transmission line loss.
The attenuation provides another constraint on the resistance values:
N R Z
( )
2
in
≤
Amax
+
R
R2 Z
1
in
(2)
where Amax
is the maximum signal gain allowable (Given in the table
above) between the primary and the differential RAS/REF input pins.
This equation assumes that constraint (1) is satisfied (no signal reflection
occurs).
R
Again, the value of
should be much smaller than Zin to decrease the
2
sensitivity to the RSLC input impedance variability.
Based on the above constraints, the following network values are recommended
for the two intended applications:
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
214
PMC [ PMC-SIERRA, INC ]
