Complete, Isolated RS-485/RS-422
Data Interface
MAX1480A
V
V
CC1
CC2
D1
V
5V
AC1
AC2
ISO V
B
IN
1
2
28
27
26
25
24
23
22
21
3
CC1
D2
4
GND1
FS
ISO RO DRV
5
Si943304
P
A
6
MAX845
MAX1487
SD
ISO DI IN
ISO DE IN
7
SHUTDOWN
V
CC3
8
R1
R2
DI
CC4
DE
ISO COM1
ISO DI DRV
9
20
19
18
17
DI
V
10
11
12
13
14
ISO V
CC2
DE
GND2
RO
ISO DE DRV
ISO COM2
ISO RO LED
R3
16
15
RO
V
CC5
ISOLATION BARRIER
GND
Figure 3. MAX1480A Low-Power Shutdown Mode
Test Circuits
ISOLATION BARRIER
ISOLATION BARRIER
(DE´)
R
( ) ARE FOR
THE MAX1480A/B/C
C
L1
V
OD
D
R
DIFF
D
V
R
RO (RO)*
R
DI´
V
OC
ID
* OPTOCOUPLER
C
L2
OUTPUTS. SEE FIGURES 1
AND 2 FOR DETAILED BLOCK
DIAGRAM AND TYPICAL
APPLICATION CIRCUIT.
Figure 4. Driver DC Test Load
Figure 5. Driver/Receiver Timing Test Circuit
14 ______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
