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