+5V-Powered, Multichannel RS-232
Drivers/Receivers
+5V INPUT
16
ALL CAPACITORS = 0.1µF
0.1µF
TOP VIEW
0.1µF
1
V
CC
C1+
2
6
+10V
-10V
+5V TO +10V
VOLTAGE DOUBLER
V+
V-
0.1µF
0.1µF
3
4
C1-
C2+
C1+
V+
1
2
3
4
5
6
7
8
16
V
CC
+10V TO -10V
VOLTAGE INVERTER
5
C2-
15 GND
0.1µF
+5V
C1-
C2+
C2-
V-
14 T1
13 R1
12 R1
OUT
400kΩ
400kΩ
MAX243
IN
T1
IN
T1
T2
11
14
OUT
OUT
IN
+5V
11 T1
10 T2
TTL/CMOS
INPUTS
RS-232
OUTPUTS
T2
OUT
IN
T2
IN
7
10
12
OUT
R2
IN
9
R2
OUT
DIP/SO
R1
OUT
R1
IN
13
TTL/CMOS
OUTPUTS
RS-232
INPUTS
5kΩ
R2
OUT
8
9
R2
IN
RECEIVER INPUT R1 OUTPUT R2 OUTPUT
5kΩ
≤ -3 V
OPEN
≥ +3V
HIGH
HIGH
LOW
HIGH
LOW
LOW
GND
15
Figure 19. MAX243 Pin Configuration and Typical Operating Circuit
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