Datasheet

INPUTS
MAX3291/MAX3292
RS-485/RS-422 Transceivers with Preemphasis
for High-Speed, Long-Distance Communication
_______________________________________________________________________________________ 9
R
B
RO
C
L
ATE
A
V
ID
R
Z
N
Y
P
Z
P
Y
N
Z
N
Z
P
Y
P
Y
N
0 DIFFERENTIAL
t
PRE
t
PTND
80%
20%
50%
Figure 9. Receiver Propagation Delay Test Circuit Figure 10. Preemphasis Timing
RE
DI
DE
1k
V
CC
RO
MAX3291
MAX3292
Figure 11. Time-to-Shutdown Test Circuit
Function Tables
DI
RE
DE
1X 1
INPUTS
Z
0
OUTPUTS
Y
1
TRANSMITTING
1 00X 1
High-Z High-Z
High-Z and
SHUTDOWN
X1 0
X0 0
A-B
RE
DE
OUTPUT
RO
1
0≤ -0.2V0 X
1
High-Z and
SHUTDOWN
X1 0
Open0 X
≥ 0.2V0 X
X = Don’t care
Z = High impedance
SHUTDOWN = Low-power shutdown; driver and receiver outputs are high impedance.
INPUTS
RECEIVING
High-ZX1 1