le7920 Zarlink Semiconductor, le7920 Datasheet - Page 14

• Manufacturer Part Number: le7920
• Description: Subscriber Line Interface Circuit
• Manufacturer: Zarlink Semiconductor

TEST CIRCUITS
L-4 Long. Bal. = 20 log (V
L-T Long. Bal. = 20 log (V
S2 Open, S1 Closed
ωC
1
B. Four- to Two-Wire Insertion Loss and Balance Return Signal
S1
V
<< R
L
V
L
R
V
2
R
C
2
AB
L
L
L
V
TX
AB
L
A. Two- to Four-Wire Insertion Loss
/ V
/ V
R
2
R
2
L
V
L
L
L
R
)
AB
)
I
BRS = 20 log (V
I
L
L4-2
L2-4
Zarlink Semiconductor Inc.
V
= 20 log (V
= 20 log (V
AB
B(RING)
A(TIP)
C. Longitudinal Balance
B(RING)
A(TIP)
14
SLIC
B(RING)
A(TIP)
4-L Long. Sig. Gen. = 20 log (V
SLIC
SLIC
AGND
AB
TX
TX
RSN
VTX
/ V
S2 Closed, S1 Open
AGND
/ V
/ V
AGND
RSN
VTX
AB
RX
RX
RSN
VTX
)
)
)
R
T
R
R
RX
T
R
L
R
RX
/ V
T
S2
RX
)
R
RX
V
RX
V
RX