Datasheet

DS3150
11 of 28
Transmit Driver Monitor. If the transmit driver monitor detects a faulty transmitter, it activates the
DM output pin. When the transmitter is tri-stated (TTS = 0), the transmit driver monitor is also disabled.
The transmitter is declared to be faulty when the transmitter outputs see a load of less than about 25W.
The DM pin is only available in the TQFP package.
Transmitter Jitter Generation (Intrinsic). The transmitter meets the jitter generation requirements
of all applicable standards, with or without the jitter attenuator enabled.
Transmitter Jitter Transfer. Without the jitter attenuator enabled in the transmit side, the transmitter
passes jitter through unchanged. With the jitter attenuator enabled in the transmit side, the transmitter
meets the jitter transfer requirements of all applicable telecommunication standards in Table 1-A. See
Figure 1-8.
Table 1-C. DS3 Waveform Template
TIME (IN UNIT INTERVALS)
NORMALIZED AMPLITUDE
EQUATIONS
UPPER CURVE
-0.85 £ T £ -0.68
0.03
-0.68 £ T £ 0.36 0.5 {1 + sin[(p/2)(1 + T/0.34)]} + 0.03
0.36 £ T £ 1.4
0.08 + 0.407e
-1.84(T - 0.36)
LOWER CURVE
-0.85 £ T £ -0.36
-0.03
-0.36 £ T £ 0.36 0.5 {1 + sin[(p/2)(1 + T/0.18)]} - 0.03
0.36 £ T £ 1.4
-0.03
Table 1-D. DS3 Waveform Test Parameters and Limits
PARAMETER SPECIFICATION
Rate
44.736Mbps (±20ppm)
Line Code B3ZS
Transmission Medium Coaxial cable (AT&T 734A or equivalent)
Test Measurement Point At the end of 0 to 450 feet of coaxial cable
Test Termination
75W (±1%) resistive
Pulse Amplitude Between 0.36V and 0.85V
Pulse Shape
An isolated pulse (preceded by two zeros and
followed by one or more zeros) falls within the
curves listed in Table 1-C
.
Unframed All-Ones Power Level at
22.368MHz
Between -1.8dBm and +5.7dBm
Unframed All-Ones Power Level at
44.736MHz
At least 20dB less than the power measured at
22.368MHz
Pulse Imbalance of Isolated Pulses
Ratio of positive and negative pulses must be
between 0.90 and 1.10