XRT73L04B Datasheet, PDF (12/64 Pages) Exar Corporation – 4 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT

XRT73L04B
4 CHANNEL DS3/E3/STS-1 LINE INTERFACE UNIT
REV. 1.0.1
OPERATING MODE SELECT
PIN #
NAME
TYPE
69
SR/DR/CS
I
72
E3_0/SDO
I/O
71
E3_1/SDI
I
108
E3_2
I
107
E3_3
I
73
STS1/DS3_0
I
83
STS1/DS3_1
106
STS1/DS3_2
98
STS1/DS3_3
DESCRIPTION
Microprocessor Serial Interface - Chip Select Input/Encoder-
Decoder Disable Input:
The function of this pin depends upon whether the XRT73L04B is oper-
ating in the HOST Mode or in the Hardware Mode.
NOTE: This pin is internally pulled "High".
Hardware Mode - Receive Output Single-Rail/Dual-Rail Select:
In Hardware Mode, setting this pin “High” configures each of the four
channels to operate in the Single-Rail Mode. When each of the four
channels are configured to operate in the Single-Rail Mode, then the
Receive Section of each channel will output data via the RPOS_(n) out-
put pin.
NOTE: Tie the TNData_(n) input to GND to enable HDB3/B3ZS Encod-
ing and Decoding.
Setting this pin “Low” configures each of the four channels to operate in
the Dual-Rail Mode. When each of the four channels are configured to
operate in the Dual-Rail Mode, then the Receive Section of each chan-
nel will output data via both the RPOS_(n) and RNEG_(n) output pins.
NOTE: This input pin functions as the CS input pin, if the XRT73L04B
device has been configured to operate in the HOST Mode.
E3_Mode Select - Channel 0:
This pin has a dual function. In HOST mode, this pin functions as SDO.
E3_Mode Select - Channel 1
This pin has a dual function. In HOST mode,this pin functions as SDI.
E3_Mode Select - Channel 2
E3_Mode Select - Channel 3
Hardware Mode Operation - E3 Mode Select - Channel (n):
This input pin is used to configure Channel (n) of the XRT73L04B to
operate in the E3 or STS-1/DS3 Modes. Setting this input pin to "High"
configures Channel (n) to operate in the E3 Mode. Setting it "Low" con-
figures Channel (n) to operate in either the DS3 or STS-1 Modes,
depending upon the state of the STS-1/DS3_(n) input pin.
NOTE: This pin is internally pulled “Low” when XRT73L04B is in the
Hardware Mode.
STS-1/DS3 Select Input - Channel (n):
“High” for STS-1 and “Low” for DS3 Operation.
The XRT73L04B ignores this pin if the E3_(n) pin is set to "1".
This input pin is ignored if the XRT73L04B is operating in the HOST
Mode.
NOTE: This pin should be tied to GND if the XRT73L04B is going to be
operating in the HOST Mode, (internally pulled-down).
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