RS-485/RS-422 Transceivers with Preemphasis

for High-Speed, Long-Distance Communication

8

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DI

DE

D

5V

Y

Z

RE

RO

DE = LOW

Figure 3. Driver Timing Test Circuit

Figure 4. Shutdown Timing Diagram

DI

5V

0

0 DIFFERENTIAL

0 DIFFERENTIAL

1.5V

20%

80%

80%

1.5V

20%

OUTPUT NORMALLY LOW

OUTPUT NORMALLY HIGH

5V

0

Y, Z

Y, Z

0

1.5V

1.5V

2.3V

S2 AND S1 CLOSED, RESPECTIVELY.

2.3V

DE

Figure 5. Driver Propagation Delays

Figure 6. Driver Enable and Disable Times

RO

A +1V

B -1V

0 DIFFERENTIAL

1.5V

1.5V

OUTPUT NORMALLY LOW

OUTPUT NORMALLY HIGH

3V

0

RO

RO

0

1.5V

1.5V

1.5V

1.5V

RE

Figure 7. Receiver Propagation Delays

Figure 8. Receiver Enable and Disable Times