STEVAL-ILB001V2 STMicroelectronics, STEVAL-ILB001V2 Datasheet - Page 18

• Manufacturer Part Number: STEVAL-ILB001V2
• Description: BOARD EVAL BIPO SOLUTION FOR PFC
• Manufacturer: STMicroelectronics

Specifications of STEVAL-ILB001V2

• Mfg Application Notes: HF Ballast AppNote
• Design Resources: STEVAL-ILB001V2 Gerber Files STEVAL-ILB001V2 Schematic STEVAL-ILB001V2 Bill of Materials
• Main Purpose: Lighting, Ballast Control
• Embedded: No
• Utilized Ic / Part: L6569
• Primary Attributes: 40W HF Ballast
• Secondary Attributes: Discontinuous Mode Boost Converter
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6409; STEVAL-ILB001V2

PFC driving network
18/30
The output voltage V
Equation 20
where
the T
The shape of the transformer voltage in a half period T/2 is:
Equation 21
After the initial instant, the capacitor begins to charge and, as soon as V
current I
considering this instant t
Equation 22
where V
capacitor voltage, and vc(t
V
there are charges stored into the base of the transistor.
Equalizing the two expressions 21 and 22 at this instant, you obtain:
Equation 23
by considering V
In order to calculate t
Equation 24
calculated when the collector current I
base current I
BE
= 0.2V is base-emitter voltage when I
1
BE voltage.
V
C
B
C
0
and
=
(t
2
2.5V
), voltage on the capacitor C
b
V
is without modulation yet (as shown in
R
A
2
=4V
is the initial capacitor voltage,
are equal to zero and the storage time of the device is beginning, so
T
2
B
of the transformer at the initial instant is:
=
≅ 6V, V
t
2
I
BON
V
that is
2
) , that is the voltage variation due to the charge of the capacitor,
T
V
( )
you have:
A
t
2
B
–
=1.5V and t
(
----------------------------------- -
=
t
V
V
I
t
V
BON
A
T
A
V
T
0
–
BE
t ( )
=
=
you have:
V
T
-- -
2
C
t
+
B
V
I
=
BON
(for ωt=30°) reaches its maximum value and the
) t
C
V
2
B
•
V
0
, is the sum of two terms
C
+
2
+
A
is equal to zero and taking in consideration that
( )
2
=
t
t
V
–
2
=
ST
t
I
R
(
-------------------------------- -
BON
=
V
V
2
=
BE
+
V
A
V
.
----------------------- -
V
R
V
–
BE
M
2
+
T
-- -
2
BE
V
LI
senωt
V
+
B
is the resistor R
=
) t
C
p
Figure
V
•
0
V
C
+
0
A
v
+
C
v
( )
C
t
22).
2
( )
t
2
V
2
C
0
voltage and V
, that is the initial
C
(t)=V
T
(t) the base
AN2349
BE
is