User Manual

MAX13171E/MAX13173E/MAX13175E
Multiprotocol, Pin-Selectable
Data Interface Chipset
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As shown in Figure 16, in V.11 mode, switch S1 is
closed and switch S2 is open, presenting 104Ω across
terminals A and B. In V.35 mode, switches S1 and S2
are both closed, presenting a T-network with 104Ω dif-
ferential impedance and 153Ω common-mode imped-
ance. In high-impedance mode, switches S1 and S2
are both open, presenting a high impedance across
terminals A and B suitable for V.28 and V.10 modes.
The state of the MAX13175E’s mode-select inputs, M0,
M1, M2, and DCE/DTE determines the mode of each of
the six termination networks. Table 3 shows a cross-ref-
erence of termination mode and select input state for
each of the six termination networks within the
MAX13175E.
R2
52Ω
R3
127Ω
R1
52Ω
S1
CLOSED
A
B
S2
OPEN
(a) V.11 (b) V.35 (c) Z
A
C
B
A
B
MAX13175E
R2
52Ω
R3
127Ω
R1
52Ω
S1
CLOSED
S2
CLOSED
R2
52Ω
R3
127Ω
R1
52Ω
S1
OPEN
S2
OPEN
CC
MAX13175E MAX13175E
Figure 16. Termination Modes
PROTOCOL DCE/DTE M2 M1 M0 R1 R2 R3 R4 R5 R6
V.10/RS-423 0 0 0 0 Z Z Z Z Z Z
RS-530A 0 0 0 1 Z Z Z V.11 V.11 V.11
RS-530 0 0 1 0 Z Z Z V.11 V.11 V.11
X.21 0 0 1 1 Z Z Z V.11 V.11 V.11
V.35 0 1 0 0 V.35 V.35 Z V.35 V.35 V.35
RS-449/V.36 0 1 0 1 Z Z Z V.11 V.11 V.11
V.28/RS-232 0 1 1 0 Z Z Z Z Z Z
No Cable 0 1 1 1 V.11 V.11 V.11 V.11 V.11 V.11
V.10/RS-423 1 0 0 0 Z Z Z Z Z Z
RS-530A 1 0 0 1 Z Z Z Z V.11 V.11
RS-530 1 0 1 0 Z Z Z Z V.11 V.11
X.21 1 0 1 1 Z Z Z Z V.11 V.11
V.35 1 1 0 0 V.35 V.35 V.35 Z V.35 V.35
RS-449/V.36 1 1 0 1 Z Z Z Z V.11 V.11
V.28/RS-232 1 1 1 0 Z Z Z Z Z Z
No Cable 1 1 1 1 V.11 V.11 V.11 V.11 V.11 V.11
Table 3. MAX13175E Termination Mode Selection