Datasheet

3.0V to 5.5V, Low-Power, up to 1Mbps, True RS-232
Transceivers Using Four 0.1µF External Capacitors
Maxim Integrated 5
MAX3222/MAX3232/MAX3237/MAX3241
-7.5
-5.0
-2.5
0
2.5
5.0
7.5
0
MAX3241
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3222-04
LOAD CAPACITANCE (pF)
TRANSMITTER OUTPUT VOLTAGE (V)
2000 30001000 4000 5000
V
OUT
+
1 TRANSMITTER AT 235kbps
2 TRANSMITTERS AT 30kbps
V
OUT
-
ALL OUTPUTS LOADED WITH 3kΩ +C
L
0.1μF CHARGE-PUMP CAPACITORS
FOR ALL DATA RATES UP TO 235kbps
4
6
8
10
12
14
16
18
20
22
24
0
MAX3241
SLEW RATE
vs. LOAD CAPACITANCE
MAX3222-05
LOAD CAPACITANCE (pF)
SLEW RATE (V/μs)
2000 30001000 4000 5000
+SLEW
-SLEW
0
5
10
15
20
25
30
35
45
40
0
MAX3241
SUPPLY CURRENT vs. LOAD
CAPACITANCE WHEN TRANSMITTING DATA
MAX3222-06
LOAD CAPACITANCE (pF)
SUPPLY CURRENT (mA)
2000 30001000 4000 5000
235kbps
120kbps
20kbps
-7.5
-5.0
-2.5
0
2.5
5.0
7.5
0
MAX3237
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE (MBAUD = GND)
MAX3222-07
LOAD CAPACITANCE (pF)
TRANSMITTER OUTPUT VOLTAGE (V)
2000 30001000 4000 5000
1 TRANSMITTER AT 240kbps
4 TRANSMITTERS AT 15kbps
3kΩ + C
L
LOADS
V
CC
= 3.3V
0
10
20
30
50
40
60
70
0
MAX3237
SLEW RATE vs. LOAD CAPACITANCE
(MBAUD = V
CC
)
MAX3222-10
LOAD CAPACITANCE (pF)
SLEW RATE (V/μs)
500 1000 1500 2000
-SLEW, 1Mbps
+SLEW, 1Mbps
1 TRANSMITTER AT FULL DATA RATE
4 TRANSMITTERS AT 1/16 DATA RATE
3kΩ + C
L
LOAD EACH OUTPUT
V
CC
= 3.3V
-SLEW, 2Mbps
+SLEW, 2Mbps
-7.5
-5.0
-2.5
0
2.5
5.0
7.5
0
MAX3237
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE (MBAUD = V
CC
)
MAX3222-08
LOAD CAPACITANCE (pF)
TRANSMITTER OUTPUT VOLTAGE (V)
500 1000 1500 2000
1 TRANSMITTER AT FULL DATA RATE
4 TRANSMITTERS AT 1/16 DATA RATE
3kΩ + C
L
LOAD, EACH OUTPUT
V
CC
= 3.3V
2Mbps
1.5Mbps
1Mbps
2Mbps
1Mbps
1.5Mbps
0
10
20
30
40
50
60
0
MAX3237
SUPPLY CURRENT vs.
LOAD CAPACITANCE (MBAUD = GND)
MAX3222-11
LOAD CAPACITANCE (pF)
SUPPLY CURRENT (mA)
2000 30001000 4000 5000
240kbps
120kbps
20kbps
1 TRANSMITTER AT FULL DATA RATE
4 TRANSMITTERS AT 1/16 DATA RATE
3kΩ + C
L
LOADS
V
CC
= 3.3V
0
2
4
6
8
10
12
0
MAX3237
SLEW RATE vs. LOAD CAPACITANCE
(MBAUD = GND)
MAX3222-09
LOAD CAPACITANCE (pF)
SLEW RATE (V/μs)
2000 30001000 4000 5000
+SLEW
-SLEW
1 TRANSMITTER AT 240kbps
4 TRANSMITTERS AT 15kbps
3kΩ + C
L
LOADS
V
CC
= 3.3V
0
10
30
20
40
50
60
70
0
MAX3237
SKEW vs. LOAD CAPACITANCE
(t
PLH
- t
PHL
)
MAX3222-12
LOAD CAPACITANCE (pF)
1000 1500500 2000 2500
MAX
MIN
AVERAGE; 10 PARTS
SKEW (ns)
1 TRANSMITTER AT 512kbps
4 TRANSMITTERS AT 32kbps
3kΩ + C
L
LOADS
V
CC
= 3.3V
MBAUD = V
CC
_____________________________Typical Operating Characteristics (continued)
(V
CC
= +3.3V, 235kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ, T
A
= +25°C, unless otherwise noted.)