LTC1544 Linear Technology, LTC1544 Datasheet - Page 12

• Manufacturer Part Number: LTC1544
• Description: Software-Selectable Multiprotocol Transceiver
• Manufacturer: Linear Technology

APPLICATIONS
LTC1544
V.35 Interface
A typical V.35 balanced interface is shown in Figure 18. A
V.35 differential generator with outputs A and B with
ground C is connected to a differential receiver with
ground C
V.35 interface requires a T or delta network termination at
the receiver end and the generator end. The receiver
differential impedance measured at the connector must be
12
'
, inputs A
'
U
connected to A, B
INFORMATION
U
B
C
A
'
'
'
W
GENERATOR
'
50
50
connected to B. The
R1
51.5
S1
R2
51.5
S2
Figure 19. V.35 Receiver Configuration
125
LTC1344A
Figure 18. Typical V.35 Interface
124
R3
U
B
A
C
INTERCONNECTING
BALANCED
CABLE
A
B
GND
R8
6k
100
nals (A
In V.35 mode, both switches S1 and S2 inside the LTC1344A
are on, connecting the T network impedance as shown in
Figure 19. The switch in the LTC1543 is off. The 30k input
impedance of the receiver is placed in parallel with the T
network termination, but does not affect the overall input
impedance significantly.
S3
20k
20k
R4
R5
C
B
A
'
'
'
TERMINATION
'
10 , and the impedance between shorted termi-
125
CABLE
and B
R6
10k
R7
10k
LOAD
50
50
'
) and ground C
RECEIVER
LTC1543
RECEIVER
1544 F19
1544 F18
'
must be 150
15 .