Datasheet
MAX220–MAX249
+5V-Powered, Multichannel RS-232
Drivers/Receivers
32 ______________________________________________________________________________________
400kΩ
V
CC
400kΩ
GND
+5V
+5V
+5V
+5V
+5V
1
40
16
1μF
2
18
4
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
ENTA
TA1OUT
TA1IN
TA3OUT
TA3IN
6 RB5OUT
12 RA1IN
10 RA1OUT
13 RA2IN
9 RA2OUT
14 RA3IN
8 RA3OUT
15 RA4IN
7
20
RA4OUT
11
39
24
38
22
36
29
31
28
32
27
33
26
34
30ENRA
ENTB
TB1OUT
TB1IN
TB3OUT
TB3IN
RB1IN
5kΩ
25
RB5IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
ENRB
400kΩ
+5V
17
3
TA2OUT
TA2IN
+5V
23
37
TB2OUT
TB2IN
400kΩ
+5V
19
5
TA4OUT
TA4IN
+5V
21
35
TB4OUT
TB4IN
40
V
CC
ENTB
TB1IN
TB2IN
TB3IN
TB4IN
RB4OUT
RB3OUT
RB2OUT
RB1OUT
RB1IN
RB2IN
RB3IN
RB4IN
RB5IN
TB1OUT
TB2OUT
TB3OUT
TB4OUT
39
38
37
36
35
34
33
32
31
1
2
3
4
5
6
7
8
9
10
ENTA
TA1IN
TA2IN
TA3IN
TA4IN
RB5OUT
RA4OUT
RA3OUT
RA2OUT
RA1OUT
RA1IN
RA2IN
RA3IN
RA4IN
TA1OUT
TA2OUT
TA3OUT
TA4OUT
GND
TOP VIEW
MAX247
30
29
28
27
26
25
24
23
22
21
11
12
13
14
15
16
17
18
19
DIP
20
ENRA ENRB
MAX247 FUNCTIONAL DESCRIPTION
9 RECEIVERS
4 A-SIDE RECEIVERS
5 B-SIDE RECEIVERS (R
B5
ALWAYS ACTIVE)
8 TRANSMITTERS
4 A-SIDE TRANSMITTERS
4 B-SIDE TRANSMITTERS
4 CONTROL PINS
ENABLE RECEIVER A-SIDE (ENRA)
ENABLE RECEIVER B-SIDE (ENRB)
ENABLE RECEIVER A-SIDE (ENTA)
ENABLE RECEIVER B-SIDE (ENTB)
+
Figure 23. MAX247 Pin Configuration and Typical Operating Circuit