Harman Kardon HK 990/230, Service Manual

Page: 62 / 141

MAX220–MAX249
+5V-Powered, Multichannel RS-232
Drivers/Receivers
______________________________________________________________________________________
TOP VIEW
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
V
CC
GND
T1
OUT
R1
IN
C2+
C1-
V+
C1+
MAX220
MAX232
MAX232A
R1
OUT
T1
IN
T2
IN
R2
OUT
R2
IN
T2
OUT
V-
C2-
DIP/SO
V+
V-
2 +10V
C1+
C1
C2
1
3
4
5
11
10
12
9
6
14
7
13
8
T1
IN
R1
OUT
T2
IN
R2
OUT
T1
OUT
R1I
N
T2
OUT
R2
IN
+5V INPUT
C2+
-10V
C4
RS-232
OUTPUTS
RS-232
INPUTS
TTL/CMOS
INPUTS
TTL/CMOS
OUTPUTS
GND
15
5k
5k
400k
400k
+5V
+5V
+10V TO -10V
VOLTAGE INVERTER
+5V TO +10V
VOLTAGE DOUBLER
16
C3
C5
CAPACITANCE (
µ
F)
DEVICE
MAX220
MAX232
MAX232A C1
4.7
1.0
0.1
C2
4.7
1.0
0.1
C3
10
1.0
0.1
C4
10
1.0
0.1
C5
4.7
1.0
0.1
C2-
C1-
V
CC
5k
DIP/SO
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
SHDN
V
CC
GND
T1
OUT
C1-
V+
C1+
(N.C.) EN
R1
IN
R1
OUT
T1
IN
T2
IN
T2
OUT
V-
C2-
C2+
10 9
R2
OUT
R2
IN
MAX222
MAX242
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
SHDN
V
CC
GND
T1
OUT
C1-
V+
C1+
(N.C.) EN
N.C.
R1
IN
R1
OUT
N.C.
T2
OUT
V-
C2-
C2+
12
11
9
10
T1
IN
T2
IN
R2
OUT
R2
IN
MAX222
MAX242
SSOP
( ) ARE FOR MAX222 ONLY.
PIN NUMBERS IN TYPICAL OPERATING CIRCUIT ARE FOR DIP/SO PACKAGES ONLY.
V+
V-
3 +10V
C1
C2
2
4
5
6
12
11
13
7
15
8
14
9
T1IN
R1OUT
T2IN
R2OUT
T1OUT
(EXCEPT MAX220)
(EXCEPT MAX220)
R1IN
T2OUT
R2IN
+5V INPUT
C2+
-10V
C4
RS-232
OUTPUTS
RS-232
INPUTS
TTL/CMOS
INPUTS
TTL/CMOS
OUTPUTS
GND
16
5k
400k
400k
+5V
+5V
+10V TO -10V
VOLTAGE INVERTER
VCC
+5V TO +10V
VOLTAGE DOUBLER
17
C3
C5
1
10
18
SHDN
EN
(N.C.)
ALL CAPACITORS = 0.1
µ
F
C2-
C1+
C1-
TOP VIEW
Figure 5. MAX220/MAX232/MAX232A Pin Configuration and Typical Operating Circuit
Figure 6. MAX222/MAX242 Pin Configurations and Typical Operating Circuit
6 0