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XRT94L33
xr
Rev.1.2.0.
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
32
C12
TXDS3CLK_0
TXE3CLK_0
I
TTL
Transmit DS3/E3 Reference Clock Input – Channel 0 (Not
used for Mapper Applications):
The exact manner in which the user should handle this input
pin depends upon whether Channel 0 has been configured to
operate in the Mapper Mode or in the ATM UNI/PPP Mode.
If Channel 0 is configured to operate in the Mapper Mode:
If Channel 0 has been configured to operate in the Mapper
Mode, then this input pin supports no function, and should,
therefore, be connected to GND.
If Channel 0 is configured to operate in the ATM
UNI/PPP/Clear Channel Mode:
If Channel 0 (within the XRT94L33) has been configured to
operate in the ATM UNI/PPP Mode, then this input pin will
function as the timing reference clock signal for the Transmit
STS-1/DS3/E3 Framer block circuitry, provided that Channel 0
has been configured to operate in the Local Timing Mode.
If Channel 0 has been configured to operate in the DS3 Mode,
then the user is expected to apply a 44.736MHz clock signal to
this input pin. Likewise, if Channel 0 has been configured to
operate in the E3 Mode, then the user is expected to apply a
34.368MHz clock signal to this input pin.
Note:
For more information on using the XRT94L33 for
ATM UNI/PPP applications, the user should consult
the
XRT94L33
1-Channel
STS-3c/3-Channel
DS3/E3/STS-1 ATM UNI/PPP Data Sheet.
B20
TXDS3CLK_1
TXE3CLK_1
I
TTL
Transmit DS3/E3 Reference Clock Input – Channel 1 (Not
used for Mapper Applications):
The exact manner in which the user should handle this input
pin depends upon whether Channel 1 has been configured to
operate in the Mapper Mode or in the ATM UNI/PPP Mode.
If Channel 1 is configured to operate in the Mapper Mode:
If Channel 1 has been configured to operate in the Mapper
Mode, then this input pin supports no function, and should,
therefore, be connected to GND.
If Channel 1 is configured to operate in the ATM UNI/PPP
Mode:
If Channel 1 (within the XRT94L33) has been configured to
operate in the ATM UNI/PPP Mode, then this input pin will
function as the timing reference clock signal for the Transmit
STS-1/DS3/E3 Framer block circuitry, provided that Channel 1
has been configured to operate in the Local Timing Mode.
If Channel 1 has been configured to operate in the DS3 Mode,
then the user is expected to apply a 44.736MHz clock signal to
this input pin. Likewise, if Channel 1 has been configured to
operate in the E3 Mode, then the user is expected to apply a
34.368MHz clock signal to this input pin.
Note:
For more information on using the XRT94L33 for
ATM UNI/PPP applications, the user should consult
the
XRT94L33
1-Channel
STS-3c/3-Channel
DS3/E3/STS-1 ATM UNI/PPP Data Sheet.