PEB22554 SIEMENS [Siemens Semiconductor Group], PEB22554 Datasheet - Page 214

• Manufacturer Part Number: PEB22554
• Description: ICs for Communications
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

When using the optical interface with NRZ coding, the decoder is by-passed and no code
violations will be detected.
Additionally, the receive line interface contains the alarm detection for Alarm Indication
Signal AIS (Blue Alarm) and the Loss of Signal LOS (Red Alarm).
The signal at the ternary interface is received at both ends of a transformer.
Figure 44
Receiver Configuration
Table 16
Recommended Receiver Configuration Values
Parameter
R
t
Loss of Signal Detection
There are different definitions for detecting Loss of Signal alarms (LOS) in the ITU-T
G.775 and AT&T TR 54016. The QuadFALC covers all these standards. The LOS
indication is performed by generating an interrupt (if not masked) and activating a status
bit. Additionally a LOS status change interrupt is programmable via register GCR.SCI.
• Detection:
Semiconductor Group
2
1
: t
An alarm will be generated if the incoming data stream has no pulses (no transitions)
for a certain number (N) of consecutive pulse periods. “No pulse” in the digital receive
interface means a logical zero on pins RDIP/RDIN/ROID. A pulse with an amplitude
less than Q dB below nominal is the criteria for “no pulse” in the analog receive
interface (LIM1.DRS=0). The receive signal level Q is programmable via three control
bits LIM1.RIL2-0 in a range of about 900 to 50 mV differential voltage between pins
RL1/2. The number N may be set via a 8 bit register PCD. The contents of the PCD
register will be multiplied by 16, which results in the number of pulse periods, or better,
( 1 %) [ ]
1
Line
t
2
t
1
214
R
2
DS1
100
1 : 1
Characteristic Impedance 100
Functional Description T1 / J1
RL1
RL2
FALC
R
ITS10967
PEB 22554
09.98