Fail-Safe, High-Speed (10Mbps),

Slew-Rate-Limited RS-485/RS-422 Transceivers

______________________________________________________________________________________

11

Pin Description (continued)

12

8

—

12

—

A

Noninverting Receiver Input

—

—

—

—

12

A

HALF-

DUPLEX

MODE

MAX3089

FULL-

DUPLEX

MODE

FULL-DUPLEX

DEVICES

MAX3081

MAX3084

MAX3087

HALF-

DUPLEX

DEVICES

MAX3082

MAX3085

MAX3088

FUNCTION

NAME

MAX3080

MAX3083

MAX3086

Receiver Input Resistors*

—

—

6

—

—

A

Noninverting Receiver Input and Noninverting Driver Output

—

—

—

13

13

RXP

Receiver Phase. Connect RXP to GND, or leave unconnected for

receiver phase/polarity.

14

1

8

14

14

Positive Supply; 4.75V

1, 8, 13

—

—

—

—

N.C.

Not Connected. Not internally connected.

Function Tables

TRANSMITTING

INPUTS

OUTPUTS

RE

DE

DI

Z

Y

X

1

1

0

1

X

1

0

1

0

0

0

X

High-Z

High-Z

1

0

X

Shutdown

RECEIVING

INPUTS

OUTPUT

RE

DE

A-B

RO

0

X

≥ -0.05V

1

0

X

≤ -0.2V

0

0

X

Open/shorted

1

1

1

X

High-Z

1

0

X

Shutdown

TRANSMITTING

INPUT

OUTPUTS

DI

Z

Y

1

0

1

0

1

0

RECEIVING

INPUTS

OUTPUT

A-B

RO

≥ -0.05V

1

≤ -0.2V

0

Open/shorted

1

PIN

X = Don’t care

Shutdown mode, driver and receiver outputs high impedance

*(MAX3089 only.) In half-duplex mode, the driver outputs serve as receiver inputs. The full-duplex receiver inputs (A and B) will still

have a 1/8-unit load, but are not connected to the receiver.

MAX3081/MAX3084/MAX3087

MAX3080/MAX3083/MAX3086