MAX3160_09 Datasheet, PDF (16/23 Pages) Maxim Integrated Products – +3.0V to+5.5V, 1μA, RS-232/RS-485/422 Multiprotocol Transceivers

+3.0V to+5.5V, 1µA, RS-232/RS-485/422
Multiprotocol Transceivers
RS-232 Transmitters
Table 1. MAX3160
INPUTS
SHDN
RS485
RS232
0
X
1
0
1
0
1
1
DI/T1IN,
DE485/T2IN
X
0
1
X
OUTPUTS
Z(B)/T1OUT,
Y(A)/T2OUT
1/8 Unit Load
1
0
RS-485 Mode
Table 2. MAX3161
INPUTS
SHDN
RS-485/
RS-232
0
X
1
0
1
0
1
1
DI/T1IN,
DE485/T2IN
X
0
1
X
OUTPUTS
T1OUT,
T2OUT
High-Z
1
0
High-Z
Table 4. MAX3160
INPUTS
SHDN
RS-485/
RS-232
X
0
X
0
X
0
X
1
Table 5. MAX3161
SHDN
X
X
X
INPUTS
RS-485/
RS-232
0
0
0
X
1
Truth Tables
RS-232 Receivers
B/R1IN,
A/R2IN
0
1
Inputs Open
X
OUTPUTS
R1OUT,
RO/R2OUT
1
0
1
R1OUT
High-Z,
RO/R2OUT in
RS-485 mode
R1IN, R2IN
0
1
Inputs Open
X
OUTPUTS
R1OUT,
RO/R2OUT
1
0
1
R1OUT
High-Z,
RO/R2OUT in
RS-485 mode
Table 3. MAX3162
INPUTS
SHDN
TE232
0
X
X
0
1
1
1
1
T1IN,T2IN
X
X
0
1
OUTPUTS
T1OUT,
T2OUT
High-Z
High-Z
1
0
Table 6. MAX3162
INPUTS
SHDN
RE232
X
1
X
0
X
0
X
0
R1IN, R2IN
X
0
1
Inputs open
OUTPUTS
R1OUT,
R2OUT
High-Z
1
0
1
High Data Rates
The MAX3160/MAX3161/MAX3162 maintain the RS-232
±5.0V required minimum transmitter output voltage even
at high data rates. Figure 11 shows a transmitter loop-
back test circuit. Figure 12 shows a loopback test result
at 250kbps, and Figure 13 shows the same test at
1000kbps. Figure 12 demonstrates a single slew-rate
limited transmitter driven at 250kbps (FAST = GND) into
an RS-232 load in parallel with 1000pF. Figure 13 shows
a single transmitter driven at 1Mbps (FAST asserted),
loaded with an RS-232 receiver in parallel with 1000pF.
These transceivers maintain the RS-232 ±5.0V minimum
transmitter output voltage at data rates up to 1Mbps.
256 Transceivers on the Bus
The standard RS-485 receiver input impedance is 12kΩ
(one-unit load), and the standard driver can drive up to
32-unit loads. The MAX3160 has a 1/4-unit load receiv-
er input impedance (48kΩ), allowing up to 128 trans-
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