Connection Diagram

8-Pin SOIC

20048802

Top View

Ordering Information

Package

Part Number

Package Marking

Transport Media

NSC Drawing

8-Pin SOIC

LMS1485M

LMS1485M

95 Units/Rail

M08A

LMS1485MX

2.5k Units Tape and Reel

LMS1485IM

LMS1485IM

95 Units/Rail

LMS1485IMX

2.5k Units Tape and Reel

Pin Descriptions

Pin # I/O

Name

Function

1

O

RO

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

2I

RE

Receiver Output Enable: RO is enabled when RE is low; RO is in TRI-STATE when RE is high

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

N/A

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

8

N/A

V

CC

Power Supply: 4.75V

≤ V

CC

≤ 5.25V

Truth Table

DRIVER SECTION

RE

DE

DI

A

B

XH

H

H

L

XH

L

L

H

XL

X

Z

Z

RECEIVER SECTION

RE

DE

A-B

RO

LL

≥ +0.2V

H

LL

≤ −0.2V

L

HX

X

Z

L

L

H

Note: * = Non Terminated, Open Input only

X = Irrelevant

Z = TRI-STATE

H = High level

L = Low level

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