MAX220–MAX249
+5V-Powered, Multichannel RS-232
Drivers/Receivers
TOP VIEW
+5V INPUT
1.0μF
1.0μF
1.0μF
9
10
V
CC
11
15
C1+
V+
V-
+5V TO +10V
VOLTAGE DOUBLER
1.0μF
1.0μF
12
13
C1-
C2+
+10V TO -10V
VOLTAGE INVERTER
14
C2-
+5V
400kΩ
T1
+
T1IN
5
18
19
2
T2OUT
T1OUT
R2IN
1
2
3
4
5
6
7
8
9
24 T3OUT
23 R3IN
22 R3OUT
21 T4IN
20 T4OUT
19 T3IN
18 T2IN
17 R4OUT
16 R4IN
15 V-
T1OUT
T2OUT
+5V
+5V
400kΩ
T2IN
T3IN
1
T2
R2OUT
T1IN
TTL/CMOS
INPUTS
RS-232
OUTPUTS
MAX238
400kΩ
R1OUT
R1IN
24
T3OUT
T4OUT
T3
400kΩ
T4
+5V
GND
20
V
21 T4IN
CC
C1+ 10
V+ 11
14 C2-
C1- 12
13 C2+
6
4
R1OUT
R1IN
7
3
R1
R2
5kΩ
R2IN
5kΩ
R3IN
5kΩ
R4IN
5kΩ
DIP/SO
R2OUT
TTL/CMOS
OUTPUTS
RS-232
INPUTS
R3OUT
R4OUT
23
16
22
17
R3
R4
GND
8
ꢁigure ±6. MAX238 Pin Configuration and Typical Operating Circuit
Maxim Integrated
25