XRT72L54 Datasheet, PDF (35/484 Pages) Exar Corporation – FOUR CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

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PRELIMINARY
PIN DESCRIPTION
PIN #
PIN NAME
F2
RxPOS[0]
F3
RxNEG[0]
F4
VDD
F17
VDD
XRT72L54
FOUR CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
REV. P1.1.2
TYPE
I
I
****
****
DESCRIPTION
Receive Positive Data Input:
The exact role of this input pin depends upon whether the Framer is
operating in the Unipolar or Bipolar Mode.
Unipolar Mode:
This input pin functions as the "Single-Rail" input for the "incoming" E3
data stream. The signal at this input pin will be sampled and latched
(into the Receive DS3/E3 Framer) on the "user-selected" edge of the
RxLineClk signal.
Bipolar Mode:
This input functions as one of the dual rail inputs for the incoming AMI/
HDB3 encoded DS3 or E3 data that has been received from an external
Line Interface Unit (LIU) IC. RxNEG functions as the other dual rail input
for the Framer. When this input pin is asserted, it means that the LIU
has received a "positive polarity" pulse from the line.
Receive Negative Data Input:
The exact role of this input pin depends upon whether the Framer is
operating in the Unipolar or Bipolar Mode.
Unipolar Mode:
This input pin is inactive, and should be pulled ("low" or "high") when the
Framer is operating in the Unipolar Mode.
Bipolar Mode:
This input pin functions as one of the dual rail inputs for the incoming
AMI/HDB3 encoded DS3 or E3 data that has been received from an
external Line Interface Unit (LIU) IC. RxPOS functions as the other dual
rail input for the Framer. When this input pin is asserted, it means that
the LIU has received a "negative polarity" pulse from the line.
Power Supply +3.3v ± 5%
Power Supply +3.3v ± 5%
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