Datasheet
MAX220–MAX249
+5V-Powered, Multichannel RS-232
Drivers/Receivers
30 ______________________________________________________________________________________
400kΩ
V
CC
400kΩ
400kΩ
GND
+5V
+5V
+5V
+5V
+5V
40
17
1μF
3
18
4
19
5
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
TA2OUT
TA2IN
TA3OUT
TA3IN
TA4OUT
TA4IN
1
11 RA1IN
10 RA1OUT
12 RA2IN
9 RA2OUT
13 RA3IN
8 RA3OUT
14 RA4IN
7 RA4OUT
15 RA5IN
6
20
RA5OUT
23
37
22
36
21
35
29
30
28
31
27
32
26
33
25
34
TB2OUT
TB2IN
TB3OUT
TB3IN
TB4OUT
TB4IN
RB1IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
RB5IN
RB5OUT
+5V
+5V
400kΩ
16
2
TA1OUT
TA1IN
24
38
TB1OUT
TB1IN
+5V
+5V
40 V
CC
ENT
TB1IN
TB2IN
TB3IN
TB4IN
RB5OUT
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
ENR
TA1IN
TA2IN
TA3IN
TA4IN
RA5OUT
RA4OUT
RA3OUT
RA2OUT
RA1OUT
RA1IN
RA2IN
RA3IN
RA4IN
RA5IN
TA1OUT
TA2OUT
TA3OUT
TA4OUT
GND
TOP VIEW
MAX245
30
29
28
27
26
25
24
23
22
21
11
12
13
14
15
16
17
18
19
DIP
20
MAX245 FUNCTIONAL DESCRIPTION
10 RECEIVERS
5 A-SIDE RECEIVERS (R
A5
ALWAYS ACTIVE)
5 B-SIDE RECEIVERS (R
B5
ALWAYS ACTIVE)
8 TRANSMITTTERS
4 A-SIDE TRANSMITTERS
2 CONTROL PINS
1 RECEIVER ENABLE (ENR)
1 TRANSMITTER ENABLE (ENT)
39
+
ENR
ENT
Figure 21. MAX245 Pin Configuration and Typical Operating Circuit