CS61305A-IL1 Cirrus Logic, Inc., CS61305A-IL1 Datasheet - Page 25

• Manufacturer Part Number: CS61305A-IL1
• Description: T1/E1 line interface
• Manufacturer: Cirrus Logic, Inc.

APPLICATIONS
Line Interface
Figure A1 illustrates the external components for
the line interface circuitry and Table A1 shows
the specific components for each application.
Figures A2-A4 show typical T1 and E1 line inter-
face application circuits. Figure A2 illustrates a
T1 interface in the Host Mode. Figure A3 illus-
trates a 120
DS157PP3
Note: Refer to Table A3 for specific transformer recommendations.
Frequency
1.544 (T1) CXT6176
2.048 (E1) CXT8192
MHz
E1 interface in the Hardware
Crystal
XTL
CS61305A
Cable
100
120
75
Table A1. External Component Values
Figure A1. Line Interface Circuitry
RRING
TRING
R1 and R2 LEN2/1/0
RTIP
TTIP
200
240
150
16
13
19
20
0/1/1 - 1/1/1
0.47 F R3
R1
R2
0/0/0
0/0/0
0/0/1
0/0/1
0/0/0
0/0/0
0/0/1
0/0/1
Mode. Figure A4 illustrates a 75
in the Extended Hardware Mode.
The receiver transformer has a grounded center
tap on the IC side. Resistors between the RTIP
and RRING pins to ground provide the termina-
tion for the receive line.
R4
1
3
5
6
2
2CT:1
T1 turns
T1
1:1.15
1:1.26
ratio
1:2.3
1:2
1:2
1:1
1:2
1:1
1:2
1:1
1:2
1
2
6
5
RECEIVE
LINE
TRANSMIT
LINE
R3 and R4
14.3
9.4
9.4
8.7
9.4
15
10
0
0
0
0
Return Loss
Typical TX
CS61305A
(dB)
0.5
0.5
0.5
0.5
20
28
12
30
24
12
5
E1 interface
25