Datasheet

MAX3140
SPI/MICROWIRE-Compatible UART with Integrated
True Fail-Safe RS-485/RS-422 Transceivers
8 _______________________________________________________________________________________
Typical Operating Characteristics
(V
CC
= +5V, T
A
= +25°C, unless otherwise noted.)
1000
900
0
-40 -20 40 60 100
UART SUPPLY CURRENT
vs. TEMPERATURE
200
100
800
700
MAX3140-01
TEMPERATURE (°C)
SUPPLY CURRENT (μA)
020 80
600
500
400
300
1.8432MHz CRYSTAL
TRANSMITTING AT 115.2 kbps
10
9
0
-40 -20 40 60 100
UART SHUTDOWN CURRENT
vs. TEMPERATURE
2
1
8
7
MAX3140-02
TEMPERATURE (°C)
SHUTDOWN CURRENT (μA)
020 80
6
5
4
3
1.8432MHz CRYSTAL
400
50
100 10k
1000
100k 1M
UART SUPPLY CURRENT
vs. BAUD RATE
150
100
MAX3140-03
BAUD RATE (bps)
SUPPLY CURRENT (μA)
200
250
350
300
TRANSMITTING
1.8432 MHz
CRYSTAL
STANDBY
700
600
0
01 3
4
5
UART SUPPLY CURRENT vs.
EXTERNAL CLOCK FREQUENCY
100
500
MAX3140-04
EXTERNAL CLOCK FREQUENCY (MHz)
SUPPLY CURRENT (μA)
2
400
300
200
0
10
05
RS-485 OUTPUT CURRENT
vs. RECEIVER OUTPUT LOW VOLTAGE
20
60
MAX3140-07
OUTPUT LOW VOLTAGE (V)
OUTPUT CURRENT (mA)
3
40
30
2
50
14
90
80
0
0 0.20.1 0.6 0.7
0.8
1.0
TX, RTS, DOUT OUTPUT CURRENT
vs. OUTPUT LOW VOLTAGE
10
70
MAX3140-05
OUTPUT LOW VOLTAGE (V)
OUTPUT SINK CURRENT (mA)
0.3 0.50.4 0.9
60
50
40
30
20
RTS
TX
DOUT
300
-60 100
RS-485 TRANSCEIVER NO-LOAD
SUPPLY CURRENT vs. TEMPERATURE
350
325
525
MAX3140-06
TEMPERATURE (°C)
NO-LOAD SUPPLY CURRENT (μA)
40
450
425
375
400
060
500
475
-40 -20 20 80
A: SRL = GND
B: SRL = OPEN OR V
CC
A
A
B
DE = V
CC
DE = GND
B
0
5
05
RS-485 OUTPUT CURRENT
vs. RECEIVER OUTPUT HIGH VOLTAGE
10
30
MAX3140-08
OUTPUT HIGH VOLTAGE (V)
OUTPUT CURRENT (mA)
3
20
15
2
25
14
0
2
-60 100
RS-485 TRANSCEIVER SHUTDOWN
CURRENT vs. TEMPERATURE
4
6
20
MAX3140-09
TEMPERATURE (°C)
SHUTDOWN CURRENT (nA)
40
12
14
10
8
060
16
18
-40 -20 20 80