XRT82D20IW Exar Corporation, XRT82D20IW Datasheet - Page 18

• Manufacturer Part Number: XRT82D20IW
• Description: IC LIU EI SGL 28SOJ
• Manufacturer: Exar Corporation

Specifications of XRT82D20IW

• Product: Framer
• Lead Free Status / RoHS Status: Contains lead / RoHS Compliant

XRT82D20
SINGLE CHANNEL E1 LINE INTERFACE UNIT
The design of the XRT82D20 permits the user to transformer-couple the Receive Section to the line. As
mentioned earlier, the specifications for E1 require 75Ω termination loads, when transmitting over coaxial
cable, and 120Ω loads, when transmitting over twisted-pair.
methods that the user can employ to interface the Receiver of the XRT82D20 to the line.
F
A
1.5
IGURE
PPLICATIONS AND
R Load
75 Ω
Source
Signal
75 Ω
12. R
Interfacing the Receive Section to the Line
ECOMMENDED
75 Ω Coax
75 Ω Coax
5 V
OPERATION ONLY
S
CHEMATIC FOR
1.36 : 1
1 : 2
T
RANSFORMER
15.4 Ω
15.4 Ω
17
270 Ω
270 Ω
-C
OUPLING THE
Figure 12
RRING
TRING
RTIP
Rx Input
Tx Output
TTIP
XRT82D20
and
Figure 13
RPOS/RData
TNEG/CODE
TPOS/TData
RNEG/LCV
TO THE
TxLEV
TGND
AGND
TVDD
AVDD
RClk
TClk
present the various
L
10 µF
INE FOR
REV. 1.0.8
75 O
0.11 µF
+5 V
HM