Datasheet

MAX3140
SPI/MICROWIRE-Compatible UART with Integrated
True Fail-Safe RS-485/RS-422 Transceivers
30 ______________________________________________________________________________________
R
Z
Y
B
A
RO
RTS
TX
RX
V
CC
SHDN
CTS
IRQ
DI
DE
RE*
RXP
TXP
X1
μP
X2
SRL
D
FULL-DUPLEX
RS-422 I/O
UART
*NOTE: TO SHUT DOWN THE RS-485 TRANSCEIVER, DRIVE RE SEPARATELY WITH AN I/O OF A μP.
MAX3140
H/F
V
CC
10k
DIN
DOUT
SCLK
CS
Figure 26. Typical Full-Duplex Operating Circuit
120Ω
120Ω
R
D
RO
RE
DE
DI
A
B
120Ω
120Ω
DI
RO RO
RO
DE
RE
RE
RE
Z
Z
Y
Y
A
A
A
BB
B
D
R
R
R
MAX3140
Figure 27. Typical Full-Duplex RS-422 Network