CX28331-1X CONEXANT [Conexant Systems, Inc], CX28331-1X Datasheet - Page 40

• Manufacturer Part Number: CX28331-1X
• Description: Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit
• Manufacturer: CONEXANT [Conexant Systems, Inc]

2.0 Functional Description
2.2 Transmitter
2.2.4 Alarm Indication Signal (AIS) Generator
Figure 2-7. AIS Signal
2.2.5 Transmit Monitor Block (CX2833i-3x Only)
2-8
8333_009
(output voltage)
(output voltage)
NEGATIVE
POSITIVE
TLINEN
TLINEP
PULSE
PULSE
When TAIS is asserted, an AIS replaces the transmit data at TPOS and TNEG.
The E3 type of AIS signal (all 1s) is supported. In three-level signal form, this is a
continuously alternating positive and negative pulse stream, as if the transmit data
were a continuous string of logical 1s.
replace single symbols within a data stream. When the encoder is disabled
(ENDECDIS = 1), the TAIS mode maintains the proper phase, based upon the
polarity of the last 1 received.
loopback.
The transmit monitor inputs (TMONP and TMONM) are designed to monitor the
line driver outputs (TLINEP and TLINEM/N) for pulses and to assert a Loss Of
Signal (TLOS) indicator when no output pulse has been detected for 32 TCLK
periods. After TLOS is asserted, it will not deassert until a pulse is again
detected. The transmit monitor is an independent function in which TMONP and
TMONM must be externally connected to TLINEP and TLINEM/N, respectively.
A special pin (TMONTST) is available for testing board-level functionality
downstream from the TLOS outputs. When TMONST is high it will assert all
TLOS channel outputs. TLOS outputs are active high when the monitor inputs do
not detect a signal.
The TAIS pin has the same data latency as the TX data pins and can be used to
The AIS signal follows the same path as the TX data during remote or local
Conexant
Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit
Figure 2-7
illustrates the AIS signal.
CX28331/CX28332/CX28333
100985A