Cirrus Logic CS61880 - Manual (Page 51)

CS61880
DS450PP3 51
Figure 17. Internal TX, External RX Impedance Matching
+
RGND
0.1
µ
F
+3.3V
RV+
T1 1:2
REF
T R I N G
T T I P
T2 1:1.15
R T I P
R R I N G
R1
R2
13.3k
Ω
GND
CBLSEL
TV+
VCCIO
+3.3V
+
TGND
+
0.1
µ
F
GNDIO
NC
75
Ω
Cable
120
Ω
Cable
GND
1k
Ω
1k
Ω
TRANSMIT
LINE
RECEIVE
LINE
0.1
µ
F
0.1
µ
F
Note 1
Note 1
Note 2
68
µ
F
CS61880
One Channel
Notes: 1)Required Capacitor between each TV+, RV+, VCCIO and TGND, RGND, GNDIO
respectively.
2)Common decoupling capacitor for all TVCC and TGND pins.
Component E1 75
Ω
Coaxial Cable E1 120
Ω
Twisted Pair Cable
R1 (
Ω
) 9.31 15
R2 (
Ω
) 9.31 15