Datasheet

MAX31911
Industrial, Octal, Digital Input
Translator/Serializer
10Maxim Integrated
Table 2. Recommended Components
Applications Information
EMC Standards Compliance
The external components shown in Figure 1 allow the
device to operate in harsh industrial environments.
Components were chosen to assist in suppression
of voltage burst and surge transients, allowing the
system to meet or exceed international EMC require-
ments. Table 2 lists an example device for each com-
ponent in Figure 1. The system shown in Figure 1,
using the components shown in Table 2, is designed
to be robust against IEC fast transient burst, surge,
conducted RFI specifications, and ESD specifica-
tions (IEC 61000-4-4, -5, -6, and -2).
Figure 1. Typical EMC Protection Circuitry
COMPONENT DESCRIPTION REQUIRED/RECOMMENDED/OPTIONAL
C0 4.7nF, 2kV polypropylene capacitor Recommended
C1
10FF, 60V ceramic capacitor
Required
C3 100nF, 10V ceramic capacitor Recommended
C4 4.7µF, 10V low ESR ceramic capacitor Required
C5 100nF, 100V ceramic capacitor Recommended
D0 36V fast zener diode (ZSMB36) Recommended
D1 General-purpose rectifier (IN4007)
Optional: For reverse polarity protection.
This diode alternatively can be placed in
series with the field supply (24V).
R1
150I, 1/3W MELF resistor
Recommended
R
INX
2.2kI, 1/4W MELF resistor
Required
R
REF
15kI, 1/8W resistor
Required
GND
MODESEL
DB1
DB0
5VOUT
SIN
CLK
CS
SOUT
FAULT
CLK
CS
SOUT
FAULT
ISOLATION
JUMPERS TO
5VOUT
AND GND
C4C3
VDD_LOGIC
R
REF
0V
R
INX
f
IN1–8
RIREF
IN1–8
RT1–8
D1
V
CC24V
MAX31911
R1
24V
D0 C1
C0
C0 C5
EARTH
EARTH
Note: For higher EMC performance, a 1nF, 1000V capacitor can be added from nodes f
IN1–IN8
to earth.