ncp1395 ON Semiconductor, ncp1395 Datasheet - Page 19

• Manufacturer Part Number: ncp1395
• Description: High Performance Resonant Mode Controller
• Manufacturer: ON Semiconductor

following conditions:
•
•
•
•
we want to implement skip cycle through the fast fault
input on the NCP1395A, we cannot activate the soft−start
every time the feedback pin stops the operations in low
power mode. Therefore, when the fast fault pin is released,
Please note that the soft−start will be activated in the
The fast fault input undergoes a special treatment. Since
A startup sequence
During auto−recovery burst mode
A brown−out recovery
A temperature shutdown recovery
Figure 42. Soft−Start Behavior
http://onsemi.com
−10.0
−20.0
NCP1395A/B
20.0
10.0
177
175
173
171
169
0
1
ires1
19
SS Action
200u
2
Figure 43. A Typical Startup Sequence on an LLC
vout
no soft−start occurs to offer the best skip cycle behavior.
However, it is very possible to combine skip cycle and true
fast fault input, e.g. via ORing diodes driving pin 13. In that
case, if a signal maintains the fast fault input high long
enough to bring the feedback level down (that is to say
below 0.6 V) since the output voltage starts to fall down,
then the soft−start is activated after the release of the pin.
12 V power supply, the soft−start is always activated upon
the fast fault input release, whatever the feedback
condition is.
In the B version tailored to operate from an auxiliary
Target is
reached
600u
time in seconds
Converter
1.00m
1.40m
Ires
Vout
1.80m
1
2