4

TGoddard/SP332/9617R0

SP332 RS-232/RS-485 Multi-Mode Serial Transceiver

© Copyright 2000 Sipex Corporation

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

1.5V

1.5V

+3V

0V

B

A

0V

DI

DRIVER

OUTPUT

DIFFERENTIAL

OUTPUT

Figure 6. RS-485 Driver Propagation Delays

Figure 7. RS-485 Receiver Propagation Delays

A – B

R

0V

1.5V

1.5V

0V

INPUT

OUTPUT