Datasheet

MAX253
Transformer Driver for
Isolated RS-485 Interface
Maxim Integrated | 14www.maximintegrated.com
10μF
6N136
MAX253
D1
D2
GND1 GND2
V
CC
4
27
8
1
SD
6
6N136
6N136
10μF
79 L12
78L05
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
CONVST
V
DD
V
SS
CLOCK
DATA
AIN
VREF
GND
MAX176
3kΩ
3kΩ
470Ω
0.1μF10μF
0.1μF
10μF
0.1μF
10μF
5V
200Ω
200Ω
8.2kΩ
74HC04
7
6
5
4
3
2
1
15
16
QH
QG
QF
QE
QD
QC
QB
QA
SER
SCK
RCK
SCLR
14
11
12
10
74HC595
13 8
5V
0.1μF
D11(MSB)
D10
D9
D8
5V
7
6
5
4
3
2
1
15
16
QH
QG
QF
QE
QD
QC
QB
QA
SER
SCK
RCK
SCLR
14
11
12
10
74HC595
13 8
5V
0.1μF
D7
D6
D5
D4
D3
D2
D1
D0(LSB)
5V
74HC04
ON/OFF
START
INPUT CLOCK
1CT : 1.5CT : 3CT*
4 x 1N5817
V
IN
5V
SIGNAL
GROUND
ANALOG
INPUT
ISO
5V
ISO
-12V
8
QH′
ISOLATION
BARRIER
*SEE TABLE 2
Figure 10. Typical Isolated ADC Application