Datasheet

MAX3140
SPI/MICROWIRE-Compatible UART with Integrated
True Fail-Safe RS-485/RS-422 Transceivers
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V
CC
R
Z
Y
RO
RTS
TX
RX
V
CC
H/F
SHDN
CTS
IRQ
DI
DE
RE*
RXP
TXP
X1
μP
X2
SRL
100k
D
HALF-DUPLEX
RS-485 I/O
UART
+5V
*NOTE: TO SHUT DOWN THE RS-485 TRANSCEIVER, DRIVE RE SEPARATELY.
V
CC
10k
MAX3140
DIN
DOUT
SCLK
CS
Figure 24. Typical Half-Duplex Operating Circuit
DI RO DE
RE
A
Z
RE
RERE
RO
RO
RO
DI
DI
DI
DE
DE
DE
D
D
D
R
R
R
B
B
B
A
A
Y
120Ω
120Ω
D
R
MAX3140
Figure 25. Typical Half-Duplex RS-485 Network