+3.3V Multiprotocol Software-Selectable

Cable Terminators and Transceivers

10

______________________________________________________________________________________

networks are configured to provide 100

Ω differential

impedance and 150

Ω common-mode impedance to ter-

minate the MAX3170 V.35 transmitter outputs and receiv-

er inputs.

Termination Mode Selection

The mode-select pins M0, M1, M2, and DCE/DTE control

the state of the five termination networks (Table 1). The

mode-select table of the MAX3172/MAX3174 is compati-

ble with the MAX3170 mode-select table so that the M0,

M1, M2, and DCE/DTE pins can be connected to the cor-

responding pins on the MAX3170. For example, M2 = 1,

M1 = 0, M0 = 0 corresponds to V.35 mode for both the

MAX3172/MAX3174 and the MAX3170 clock/data trans-

ceiver chip.

R4/T4 Mode Selection

The MAX3172/MAX3174 include a transceiver for use in

applications requiring an extra serial handshake signal

(for example, local loopback). The transceiver can be

PROTOCOL

M2

M1

M0

DCE/

DTE

INVERT

T4

R4

Not Used (Default V.11)

0

0

0

0

0

Z

V.10

RS-530A

0

0

1

0

0

Z

V.10

RS-530

0

1

0

0

0

Z

V.10

X.21

0

1

1

0

0

Z

V.10

V.35

1

0

0

0

0

Z

V.28

RS-449/V.36

1

0

1

0

0

Z

V.10

V.28/RS-232

1

1

0

0

0

Z

V.28

No Cable

1

1

1

0

0

Z

Z

Not Used (Default V.11)

0

0

0

1

0

V.10

Z

RS-530A

0

0

1

1

0

V.10

Z

RS-530

0

1

0

1

0

V.10

Z

X.21

0

1

1

1

0

V.10

Z

V.35

1

0

0

1

0

V.28

Z

RS-449/V.36

1

0

1

1

0

V.10

Z

V.28/RS-232

1

1

0

1

0

V.28

Z

No Cable

1

1

1

1

0

Z

Z

Not Used (Default V.11)

0

0

0

0

1

V.10

Z

RS-530A

0

0

1

0

1

V.10

Z

RS-530

0

1

0

0

1

V.10

Z

X.21

0

1

1

0

1

V.10

Z

V.35

1

0

0

0

1

V.28

Z

RS-449/V.36

1

0

1

0

1

V.10

Z

V.28/RS-232

1

1

0

0

1

V.28

Z

No Cable

1

1

1

0

1

Z

Z

Not Used (Default V.11)

0

0

0

1

1

Z

V.10

RS-530A

0

0

1

1

1

Z

V.10

RS-530

0

1

0

1

1

Z

V.10

X.21

0

1

1

1

1

Z

V.10

V.35

1

0

0

1

1

Z

V.28

RS-449/V.36

1

0

1

1

1

Z

V.10

V.28/RS-232

1

1

0

1

1

Z

V.28

No Cable

1

1

1

1

1

Z

Z

Table 3. R4/T4 Mode-Select Table