iC-DXC
DIGITAL SENSOR I/O DRIVER
Rev A0.8, Page 9/11
CIRCUIT PROTECTION
The iC-DXC is reverse polarity protected via internal slow, and injected charge through disturbances may
circuitry. As far as the maximum voltage ratings are in general result in capacitor voltage exceeding maxi-
not exceeded, no possible supply combination at the mum ratings, leading to malfunction or destruction of
line side pins (VB, GND and OUT) can damage the circuitry and associated parts. Thus EMC require-
chip.
ments will afford more external circuitry. Figure 7
shows the iC-DXC with the additional protective device
Since the chip current consumption is relatively low, D1, D2 and D3.
discharging of the backup capacitor C1 can be very
8
VB
7
C1
REG
5V
VREF
1μF
High Side Switch
+
<150
C
-
8
1
VOUT
36V
C3
100nF..
OUT
7
6
DIGITAL INPUT
C2
1nF
OE
3
2
5
4
&
&
PSD36
D2
PSD36
D3
36V
NIN
D1
PSD36
GND
3
1
iC-DXC
Low Side Switch
MON
CFO
5
4
2
6
VRH
VRL
FILT
=1
++
-
+
EPAD
Figure 7: Circuit schematic showing protective devices
For over-voltage protection, the suppressor diodes the backup capacitor C1 should be kept small. A typi-
D1,D2 and D3 absorbs transients on supply line in- cal 100nF value is normally OK.
jected externally on the cable. Clamp voltage of the
diodes should be rated slightly above maximum speci-
fied supply voltage.
These currents can be passed to ground or to VB Suggested protective devices
by the internal ESD diodes of the iC-DXC. Whereas At VBmax of 36V, suppressor diodes with a breakdown
negative current injection will simply be drained off to voltage from 36V has to be chosen in order to minimize
ground, positive current injection will charge capacitor the energy in iC-DXC for higher Voltages. For example
C1 further to higher voltages. If not suppressor diodes Diode type like Vishay GSOT36C or PJSD36W from
nor any other over-voltage protection is implemented, Panjit should be enough as protection.
ICHAUS [ IC-HAUS GMBH ]
