max253cuat Maxim Integrated Products, Inc., max253cuat Datasheet - Page 8

• Manufacturer Part Number: max253cuat
• Description: Max253 Transformer Driver For Isolated Rs-485 Interface
• Manufacturer: Maxim Integrated Products, Inc.

Transformer Driver for
Isolated RS-485 Interface
Figure 5. Typical RS-232 Application Circuit
8
_______________________________________________________________________________________
V
5V
T1
T2
T4
T5
R1
R2
R3
R4
R5
T3
*74HC04 OR EQUIVALENT
**
IN
IN
4N25 LOWER SPEED, LOWER COST ALTERNATE OPTOCOUPLER CONFIGURATIONS (FOR DATA RATES BELOW 9.6kbps)
IN
IN
IN
OUT
OUT
OUT
OUT
OUT
IN
*74HC04
5 X 3.3k
74HC04
74HC04
74HC04
74HC04
74HC04
74HC04
74HC04
74HC04
74HC04
SEE TABLE 2
ON / OFF
*74HC04
T
IN
C1
0.1µF
390
5
4
N.C.
SD
390
390
390
390
390
GND1 GND2
2
MAX253
1
2
4N25
V
CC
6
7
6
D1
D2
FS
1N5711
3
1
8
4
5
6
5
4
ISO
GND
ICT:1.3CT**
1
2
3.3k
10 x PC417
ISOLATION
BARRIER
1N5817
1N5817
ISO
T
V
IN
1
2
CC
4
6
5
R
0.1µF
OUT
C3
74HCO4
3.3k
5 x 3.3k
390
390
390
390
390
1N5711
C2
22µF
5
4
8
IN
SET
6
15
16
22
23
17
14
MAX667
6
8
7
9
6
4N25
GND
T1
T2
T3
T4
T5
R1
R2
R3
R4
R5
21
IN
IN
IN
IN
IN
OUT
OUT
OUT
OUT
OUT
1
2
4
V
SD
MAX205
CC
SHDN
OUT
ISO
GND
5
390
GND
T1
T2
T3
T4
T5
EN
2
R1
R2
R3
R4
R5
OUT
OUT
OUT
OUT
OUT
20
IN
IN
IN
IN
IN
C4
22µF
ISO 5V
3
4
2
1
19
10
5
24
18
13
V
ISO
R
CC
OUT