NCP1654_09 ONSEMI [ON Semiconductor], NCP1654_09 Datasheet - Page 20

• Manufacturer Part Number: NCP1654_09
• Description: Power Factor Controller for Compact and Robust, Continuous Conduction Mode Pre-Converters
• Manufacturer: ONSEMI [ON Semiconductor]

needed, which is 0.7 V typical in this device. When V
goes below than V
the Drive output and keeps it off till V
(1.3 V typical). When the device awakes after an off−state
(Undervoltage lockout or shutdown), the default threshold
is V
level 200 mVA, the device turns off the drive output so that
the input power is limited. The OPL is automatically
deactivated when the product (I
200 mVA level. This 200 mVA level corresponds to the
approximated input power (I
particular expression in (Equation 23).
Hence a larger hysteresis of the brown out comparator is
When the product (I
BOH
I
I
cs
L
I
@ V
L
V
.
R
bo
SENSE
R
ac
t 200 mVA
CS
t
R
SENSE
BOL
@
R
CS
cs
2 2 K
(0.7 V typical), the device turns off
V
⋅ V
@ p
RCS
@ K
ac
p
bo
BO
BO
L
) is greater than a permissible
V
⋅ V
@ 50 2 mVA
Before Device Operates
in
@ V
cs
R
R
ac
ICS
IN
boU
boL
⋅ V
ac
) to be smaller than the
bo
t 200 mVA
) is lower than the
bo
3
4
Vbo
exceeds V
CS
Figure 46. Over−Power Limitation
R
+
−
SENSE
Figure 45. Brown−Out Protection
(eq. 23)
V
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in
C
BOH
Current Mirror
BO
bo
I
L
20
Vbo
I
CS
4
Overpower Limitation (OPL)
dependent. Sense current I
I
Input voltage signal V
The product (I
power (I
Bias the Controller
decoupling capacitor next to the V
operation. When the NCP1654 operates in follower boost
mode, the PFC output voltage is not always regulated at a
particular level under all application range of input voltage
and load power. It is not recommended to make a
low−voltage bias supply voltage by adding an auxiliary
winding on the PFC boost inductor. Alternatively, it is
recommended to get the V
2
L
nd
+ I
This is a second OCP with a threshold that is line
It is recommended to add a typical 1 nF to 100 nF
and hence represents the input current approximately.
−stage power conversion stage.
After Device Operates
L
R
SENSE
R
+
L
-
CS
⋅ V
ac
BO
V
V
cs
). It is illustrated in Figure 46.
boH
boH
⋅ V
/ V
= 1.3 V, V
bo
boL
bo
) represents an approximated input
>200 mVA?
represents the rms input voltage.
cs
boL
represents the inductor current
+
cc
= 0.7 V
biasing supply from the
+
cc
OPL
pin for proper