XRT72L13 Datasheet, PDF (45/370 Pages) Exar Corporation – M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC

áç
PRELIMINARY
PIN DESCRIPTIONS
PIN #
NAME
184
RLOL
185
ExtLOS
186
VDD
187
RxVCOup
188
RxVCOdown
189
RxLineClk
XRT72L13
M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC
REV. P1.0.6
TYPE
I
I
****
O
O
I
DESCRIPTION
Receive Loss of Lock Indicator - from the XRT7300 DS3/E3 Line
Interface Unit IC.
This input pin is intended to be connected to the RLOL (Receive Loss
of Lock) output pin of the XRT7300 Line Interface Unit IC. The user
can monitor the state of this pin by reading the state of Bit 1 (RLOL)
within the Line Interface Scan Register (Address = 0x81).
If this input pin is "low", then it means that the "clock recovery phase-
locked-loop" circuitry, within the XRT7300 is properly locked onto the
incoming DS3 data-stream; and is properly recovering clock and data
from this DS3 data-stream. However, if this input pin is "high", then it
means that the phase-locked-loop circuitry, within the XRT7300 has
lost lock with the incoming DS3 data-stream, and is not properly
recovering clock and data.
For more information on the operation of the XRT7300 DS3/E3 Line
Interface Unit IC, please consult the "XRT7300 DS3/E3 Line Interface
Unit" data sheet.
NOTE: This output pin can be used for a variety of other purposes if
the XRT7300 DS3/E3 LIU is not used.
Receive LOS (Loss of Signal) Indicator Input (from XRT7300 LIU
IC).
This input pin is intended to be connected to the RLOS (Receive Loss
of Signal) output pin of the XRT7300 Line Interface Unit IC. The user
can monitor the state of this pin by reading the state of Bit 0 (RLOS)
within the Line Interface Scan Register (Address = 0x81).
If this input pin is "low", then it means that the XRT7300 is currently
NOT declaring an "LOS (Loss of Signal) condition. However, if this
input pin is "high", then it means that the XRT7300 is currently declar-
ing an LOS (Loss of Signal) condition.
For more information on the operation of the XR-T7300 DS3/E3 Line
Receiver IC, please consult the "XRT7300 DS3/STS-1/E3 Line Inter-
face Unit IC" data sheet.
NOTE: Asserting the RLOS input pin will cause the XRT72L13 M13
Multiplexer/Framer to declare an "LOS (Loss of Signal) condition.
Therefore, this input pin should not be used as a general purpose
input.
Power Supply Pin
Receive VCO Frequency Increase:
Receive VCO Frequency Decrease:
Receiver LIU (Recovered) Clock:
This input signal serves three purposes:
The Receive Framer uses it to sample and "latch" the signals at the
RxPOS and RxNEG input pins (into the Receive Framer circuitry).
This input signal functions as the timing reference for the Receive
Framer block.
The Transmit Framer block can be configured to use this input signal
as its timing reference.
NOTE: This signal is the recovered clock from the external DS3 LIU
(Line Interface Unit) IC, which is derived from the incoming DS3 data.
33