+5V-Powered, Multichannel RS-232
Drivers/Receivers
+5V
1µF
TOP VIEW
1µF
20
21
V
22
C1+
C1-
CC
1µF
1µF
23
24
V+
V-
+5V TO +10V VOLTAGE DOUBLER
26
C2+
C2-
1µF
25
+10V TO -10V VOLTAGE INVERTER
43
42 41 40
6
5
4
3
2
1
44
+5V
+5V
+5V
+5V
2 T OUT
T
OUT 44
A1
B1
400k
400k
15 T IN
T
IN 30
B1
A1
R
R
R
IN
IN
IN
7
8
9
39
38
37
36
35
34
33
32
31
30
29
R
R
R
R
R
R
R
R
R
IN
A3
A2
A1
B4
B3
B2
B1
B1
B2
B3
B4
B5
IN
2 T OUT
A2
T
OUT 43
B2
IN
R
R
R
R
R
OUT 10
OUT 11
OUT 12
OUT 13
OUT 14
IN
A1
A2
A3
A4
16 T IN
A2
T
IN 29
B2
OUT
OUT
OUT
OUT
OUT
MAX244
+5V
+5V
+5V
+5V
3 T OUT
A3
T
T
OUT 42
B3
400k
400k
17 T IN
T
IN 28
B3
A3
A5
T
IN 15
IN 16
IN 17
A1
A2
A3
4 T OUT
A4
OUT 41
B4
T
T
T
T
IN
IN
B1
B2
18 T IN
T
IN 27
IN 36
A4
B4
9 R IN
R
A1
B1
18 19 20 21 22 23 24 25 26 27 28
5k
5k
5k
5k
5k
5k
PLCC
10 R OUT
R
OUT 35
A1
B1
8 R IN
R
IN 37
B2
A2
5k
MAX249 FUNCTIONAL DESCRIPTION
10 RECEIVERS
11 R OUT
R
OUT 34
B2
A2
5 A-SIDE RECEIVER
5 B-SIDE RECEIVER
7 R IN
A3
R
IN 38
B3
8 TRANSMITTERS
5k
4 A-SIDE TRANSMITTERS
4 B-SIDE TRANSMITTERS
NO CONTROL PINS
12 R OUT
A3
R
OUT 33
B3
6 R IN
A4
R
IN 39
B4
5k
13 R OUT
R
OUT 32
B4
A4
5 R IN
R
IN 40
B5
A5
5k
14 R OUT
R
OUT 31
B5
A5
GND
19
Figure 20. MAX244 Pin Configuration and Typical Operating Circuit
______________________________________________________________________________________ 29
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
