NCP1336 ONSEMI [ON Semiconductor], NCP1336 Datasheet - Page 21

• Manufacturer Part Number: NCP1336
• Description: Quasi-Resonant Current Mode Controller for High Power Universal Off-Line Supplies
• Manufacturer: ONSEMI [ON Semiconductor]

details the various time portion a hiccup is made of:
becomes easy to evaluate the burst period and its duty−cycle.
This can be done by properly identifying all time events on
Figure 8 and applying the classical formula:
•
•
The recurrence in hiccup mode can easily be adjusted by either reducing the timer or increasing the V
If by design we have selected a 22 mF V
t
t
220 ms
1
2
: I = ICC3 = 600 mA, ΔV= 15 V − 9 V = 6 V ³ t
: I = 3 mA, ΔV= 15 V − 9 V = 6 V ³ t
Figure 24. The Burst Period is Ensured by the V
Figure 23. This Case is Similar to a Short−Circuit Where V
t + CDV
I
1
CC
= 44 ms
capacitor, it
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2
=
21
CC
which leads to t
burst duty−cycle equals 50 ms / (572 ms + 50 ms) ≈ 8%,
which is good. Should the user like to further decrease or, to
the contrary, increase this duty−cycle, changing the V
capacitor is an easy job.
Capacitor Charge / Discharge Cycle
The total period duration is thus the sum of all these events
hiccup
aux
= 572 ms. If t
Does Collapse
CC
fault
capacitor. Figure 24
= 50 ms, then our
CC