VIPer50A-E/ASP-E
6 Electrical Over Stress
6
Electrical Over Stress
6.1
Electrical Over Stress Ruggedness
The VIPer may be submitted to electrical over-stress, caused by violent input voltage surges or
lightning. Following the Layout Considerations is sufficient to prevent catastrophic damages
most of the time. However in some cases, the voltage surges coupled through the transformer
auxiliary winding can exceed the V pin absolute maximum rating voltage value. Such events
DD
may trigger the V internal protection circuitry which could be damaged by the strong
DD
discharge current of the V bulk capacitor. The simple RC filter shown in Figure 23 can be
DD
implemented to improve the application immunity to such surges.
Figure 23. Input Voltage Surges Protection
D1
R1
(Optional)
R2
39R
Auxilliary winding
DRAIN
VDD
C2
-
+
C1
OSC
Bulk capacitor
22nF
13V
COMP
SOURCE
VIPerXX0
21/31
STMICROELECTRONICS [ ST ]
