3

FN6587.1

February 18, 2008

Pin Descriptions

PIN

FUNCTION

RO

Receiver output: If A - B

≥ -50mV, RO is high; If A - B ≤ -200mV, RO is low; RO = High if A and B are unconnected (floating) or shorted,

or connected to a terminated bus that is undriven.

RE

Receiver output enable. RO is enabled when RE is low; RO is high impedance when RE is high. If the Rx enable function isn’t

required, connect RE directly to GND.

DE

Driver output enable. The driver outputs, Y and Z, are enabled by bringing DE high. They are high impedance when DE is low. If the

DI

Driver input. A low on DI forces output Y low and output Z high. Similarly, a high on DI forces output Y high and output Z low.

GND

Ground connection. This is also the potential of the DFN thermal pad.

A/Y

±15kV IEC61000 ESD Protected RS-485, RS-422 level, noninverting receiver input and noninverting driver output. Pin is an input (A)

if DE = 0; pin is an output (Y) if DE = 1.

B/Z

±15kV IEC61000 ESD Protected RS-485, RS-422 level, inverting receiver input and inverting driver output. Pin is an input (B) if

DE = 0; pin is an output (Z) if DE = 1.

System power supply input (4.75V to 5.25V).

NC

No Connection.

Typical Operating Circuit

ISL3259E

0.1µF

+

D

R

7

6

8

1

2

3

4

5

GND

RO

RE

DE

DI

A/Y

B/Z

+5V

0.1µF

+

D

R

6

7

8

1

2

3

4

5

GND

RO

RE

DE

DI

A/Y

B/Z

+5V

MSOP PIN NUMBERS SHOWN

ISL3259E