xrt83l30 Exar Corporation, xrt83l30 Datasheet - Page 54

• Manufacturer Part Number: xrt83l30
• Description: Xrt83l30 -single-channel T1/e1/j1 Long-haul, Short-haul Line Interface Unit
• Manufacturer: Exar Corporation

XRT83L30
SINGLE-CHANNEL T1/E1/J1 LH/SH TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
D4
D3
D2
D1
D0
Reserved
RXRES1
RXRES0
INSBPV
TRATIO
T
ABLE
21: M
Receive External Resistor Control pin 1: In Host mode, this
bit along with the RXRES0 bit selects the value of the external
Receive fixed resistor according to the following table:
Receive External Resistor Control bit 0: For function of this bit
see description of D4 the RXRES1 bit.
Insert Bipolar Violation: When this bit transitions from "0" to
"1", a bipolar violation is inserted in the transmitted data stream.
Bipolar violation can be inserted either in the QRSS pattern, or
input data when operating in single-rail mode. The state of this bit
is sampled on the rising edge of TCLK.
N
Transformer Ratio Select: In the external termination mode,
writing a “1” to this bit selects a transformer ratio of 1:2 for the
transmitter. Writing a “0” sets the transmitter transformer ratio to
1: 2.45. In the internal termination mode the transmitter trans-
former ratio is permanently set to 1:2 and the state of this bit has
no effect.
OTE
: To ensure the insertion of a bipolar violation, a "0" should
ICROPROCESSOR
RXRES1
be written in this bit location before writing a "1".
0
0
1
1
RXRES0
0
1
0
1
51
R
EGISTER
No External Fixed Resistor
Required Fixed External
#3
RX Resistor
BIT DESCRIPTION
52.5 Ω
37.5 Ω
60 Ω
R/W
R/W
R/W
R/W
R/W
REV. 1.0.1
0
0
0
0
0