Pin Descriptions

Pin #

I/O

Name

Function

1

O

RO

be high also if the inputs (A and B) are open (non-terminated).

2I

3

I

DE

Driver Output Enable: The driver outputs (A and B) are enabled when DE is high; they are in

TRI-STATE when DE is low. Pins A and B also function as the receiver input pins (see below).

4

I

DI

Driver Input: A low on DI forces A low and B high while a high on DI forces A high and B low when

the driver is enabled.

5

NA

GND

Ground

6

I/O

A

Non-inverting Driver Output and Receiver Input pin. Driver output levels conform to RS-485 signaling

levels.

7

I/O

B

Inverting Driver Output and Receiver Input pin. Driver output levels conform to RS-485 signaling

levels.

8NA

V

CC

Power Supply: 4.75V

≤ V

Related National Low Power RS-485 Transceivers

Part Number

Temperature

Number of

Comments

Range

XCVRs on Bus

DS36C278

0˚C to +70˚C

128

Ultra Low Power Transceiver

DS36C278T

−40˚C to +85˚C

64

Ultra Low Power Transceiver

DS36C279

0˚C to +70˚C

128

Auto-Sleep Mode

DS36C279T

−40˚C to +85˚C

64

Auto-Sleep Mode

DS36C280

0˚C to +70˚C

128

Adjustable Slew Rate Control

DS36C280T

−40˚C to +85˚C

64

Adjustable Slew Rate Control

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