May11-2007

SP481E Low Power Half-Duplex RS485 Transceivers

© 2007 Sipex Corporation

4

PIN FUNCTION

Pin 1 – RO – Receiver Output.

Pin 2 – RE – Receiver Output Enable Active LOW.

Pin 3 – DE – Driver Output Enable Active HIGH.

Pin 4 – DI – Driver Input.

Pin 5 – GND – Ground Connection.

Pin 6 – A – Driver Output/Receiver Input

Non-inverting.

Pin 7 – B – Driver Output/Receiver Input Inverting.

Pin 8 – Vcc – Positive Supply 4.75V<Vcc< 5.25V.

SP481E and SP485E

Pinout (Top View)

RO 1

RE 2

DE 3

DI 4

8

7

B

6

A

5

GND

D

R

SP485

Top View

Figure 5. Driver Propagation Delays

A

B

R

R

Figure 1. RS-485 Driver DC Test Load Circuit

Figure 2. Receiver Timing Test Load Circuit

Figure 3. RS-485 Driver/Receiver Timing Test Circuit

Figure 4. RS-485 Driver Timing Test Load #2 Circuit

1k

1k

Test Point

Receiver

Output

B

A

DI

B

A

RO

15pF

500

Output

Under

Test

+3V

0V

DI

B

A

DRIVER

OUTPUT

DIFFERENTIAL

OUTPUT

0V

1.5V

1.5V

SKEW =