MAX3162 MAXIM [Maxim Integrated Products], MAX3162 Datasheet - Page 19

• Manufacturer Part Number: MAX3162
• Description: +3.0V to +5.5V, 1uA, RS-232/RS-485/422 Multiprotocol Transceivers
• Manufacturer: MAXIM [Maxim Integrated Products]

The RS-485/422 standard covers line lengths up to
4000 feet. For line lengths greater than 4000 feet, use
the repeater application shown in Figure 14.
Figure 15 shows the MAX3162 configured as an RS-
232/RS-485 protocol translator. The direction of transla-
tion is controlled through the RTS signal (R1IN). The
single-ended RS-232 receiver input signal is translated
to a differential RS-485 transmitter output. Similarly, a
Figure 10. MAX3160 RS-232 Transmitter Outputs when Exiting
Shutdown
Figure 11. Loopback Test Circuit
RS-485/422 Line Length vs. Data Length
V
V
C1
C2
CC
CC
RS-232/RS-485 Protocol Translator
C
BYPASS
SHDN
C1+
C1-
C2+
C2-
T_ IN
R_ OUT
______________________________________________________________________________________
+3.0V to+5.5V, 1µA, RS-232/RS-485/422
MAX3160
MAX3161
MAX3162
40µs/div
GND
V
CC
MAX 3160-2 FIG10
T_ OUT
5kΩ
R_ IN
V+
V-
SHDN
5V/division
T1OUT
2V/div
T2OUT
2V/div
GND
C3
C4
1000pF
Multiprotocol Transceivers
differential RS-485 receiver input signal is translated to
a single-ended RS-232 transmitter output. RS-232 data
received on R2IN is transmitted as an RS-485 signal on
Z and Y. RS-485 signals received on A and B are trans-
mitted as an RS-232 signal on T
The Typical Operating Circuit shows a standard appli-
cation for the MAX3160. The MAX3160’s output pins
are multiplexed between RS-232 and RS-485 protocols
by a microprocessor (µP). The µP also directs the shut-
down functions, enable lines, and the duplex of the
MAX3160. Data is transmitted to the MAX3100 UART
through an SPI™ port. The UART asynchronously
transfers data through the MAX3160 to the pin-selected
RS-232 or RS-485 protocol; see Table 14 for commonly
used cable connections.
SPI is a trademark of Motorola, Inc.
Figure 12. RS-232 Loopback Test Result at 250kbps, FAST =
Low
Figure 13. RS-232 Loopback Test Result at 1000kbps, FAST =
High
200ns/div
1µs/div
1OUT
M
MAX 3160-2 FIG12
ultiprotocol Bus
MAX 3160-2 FIG13
.
T
T
R
T
5V/div
R
T
5V/div
IN
OUT
OUT
OUT
IN
OUT
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