•

Balanced cables (e.g., twisted pair) are usually better

than unbalanced cables (ribbon cable, simple coax) for

noise reduction and signal quality.

•

work effectively. For distances 0.5m

≤ d ≤ 10m, CAT 3

(category 3) twisted pair cable works well and is readily

available and relatively inexpensive. For distances

mended.

•

There are three Fail-Safe scenarios, open input pins,

shorted inputs pins and terminated input pins. The first

case is guaranteed for DS90LV019. A HIGH state on

R

(one to V

Input Fail-Safe Circuit). R1 and R2 should be R

the loading to the LVDS driver . R

the impedance of the cable.

TABLE 1. Functional Table

MODE SELECTED

DE

RE

DRIVER MODE

H

H

RECEIVER MODE

L

L

TRI-STATE MODE

L

H

FULL DUPLEX MODE

H

L

TABLE 2. Transmitter Mode

INPUTS

OUTPUTS

DE

DI

DO+

DO−

HL

L

H

HH

H

L

X

X

LX

Z

Z

X = High or Low logic state

Z = High impedance state

L = Low state

H = High state

TABLE 3. Receiver Mode

INPUTS

OUTPUT

RE

(RI+) − (RI−)

L

H

L

X

HX

Z

X = High or Low logic state

Z = High impedance state

L = Low state

H = High state

TABLE 4. Device Pin Description

Pin Name

Pin #

Input/Output

Description

D

IN

2

I

TTL Driver Input

11, 12

O

LVDS Driver Outputs

9, 10

I

LVDS Receiver Inputs

R

OUT

4

O

TTL Receiver Output

RE

8

I

Receiver Enable TTL Input (Active Low)

DE

1

I

Driver Enable TTL Input (Active High)

GND

7

NA

Ground

V

CC

14

NA

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