+5V, Fail-Safe, 20Mbps, Profibus RS-485/

RS-422 Transceivers

6

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Pin Description

PIN

MAX3460/

MAX3461

MAX3462

MAX3463/

MAX3464

FULL DUPLEX

HALF

DUPLEX

NAME

FUNCTION

1

——

SHDN

Shutdown. Drive SHDN high to enter low-power shutdown mode.

22

1

RO

Receiver Output. When RE is low and (A - B)

≥ -50mV, RO is high; if (A - B) ≤

-200mV, RO is low.

3

—

2

RE

Receiver Output Enable. Drive RE low to enable RO; RO is high impedance

when RE is high. Drive RE high and DE low to enter low-power shutdown mode.

4

—

3DE

Driver Output Enable. Drive DE high to enable driver output. These outputs

are high impedance when DE is low. Drive RE high and DE low to enter low-

power shutdown mode.

53

4

DI

Driver Input. With DE high, a low on DI forces the noninverting output low and

the inverting output high. Similarly, a high on DI forces the noninverting output

high and the inverting output low.

6, 7

4

5

GND

Ground

8

——

TXP

Transmitter Phase. Connect TXP to GND, or leave unconnected for normal

phase/polarity. TXP has an internal 15µA pulldown.

95

—

Y

Noninverting Driver Output

10

6

—

Z

Inverting Driver Output

11

7

—

B

Inverting Receiver Input

12

8

—

A

Noninverting Receiver Input

13

——

RXP

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

phase/polarity. RXP has an internal 15µA pulldown.

14

1

8

Positive Supply: +4.75V

capacitor.

——

7

B

Inverting Receiver Input and Inverting Driver Output

——

6

A

Noninverting Receiver Input and Noninverting Driver Output

Typical Operating Characteristics (continued)

0

5V/div

2V/div

5V/div

0

0

DRIVER AND RECEIVER

PROPAGATION DELAYS

MAX3460-64 toc13

DI

Y, Z

RO

10ns/div

0

0

ENABLE RESPONSE TIME

MAX3460-64 toc14

DE

Y, Z

20ns/div

1V/div

5V/div

EYE DIAGRAM

10ns/div