Electronic Components Datasheet Search
  English  ▼

X  

Preview PDF HTML

AN3142 Datasheet(PDF) 29 Page - STMicroelectronics

Part # AN3142
Description  Solution for designing a 400 W fixed-off-time controlled
PDF  44 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  STMICROELECTRONICS [STMicroelectronics]
Direct Link  http://www.st.com
Logo STMICROELECTRONICS - STMicroelectronics

AN3142 Datasheet(HTML) 29 Page - STMicroelectronics

Back Button AN3142 Datasheet HTML 25Page - STMicroelectronics AN3142 Datasheet HTML 26Page - STMicroelectronics AN3142 Datasheet HTML 27Page - STMicroelectronics AN3142 Datasheet HTML 28Page - STMicroelectronics AN3142 Datasheet HTML 29Page - STMicroelectronics AN3142 Datasheet HTML 30Page - STMicroelectronics AN3142 Datasheet HTML 31Page - STMicroelectronics AN3142 Datasheet HTML 32Page - STMicroelectronics AN3142 Datasheet HTML 33Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 29 / 44 page
background image
AN3142
Designing a fixed-off-time PFC
Doc ID 17005 Rev 3
29/44
Equation 60
Where fswmin is the switching frequency on the top of the sinusoid of the input voltage at
VACmin = 90 VAC (Figure 18) and 220 ns is a corrector factor in order to consider the delay
between the ZCD and GD signal.
Considering the ratio between
Equation 60, Equation 59:
Equation 61
In the formula
Equation 59, Equation 60, the delay between the ZCD signal and the gate
drive signal is taken into account in order to increase the accuracy of the mathematical
model.
From the theory of the line modulation fixed off-time, TOFF is increasing with the line voltage
so that at maximum line voltage the condition TON>TONmin is always true [4]. This is
important in order to avoid line distortion [
5].
Figure 18.
Switching frequency function on the peak of the sinusoid input voltage
waveform and the corresponding off-time value
Now considering the two discharging resistors R and R0 of the circuit in
Figure 6, the ratio is
defined:
Equation 62
max
max
min
ON
max
OFF
k
1
k
T
)
VAC
(
T
−
⋅
=
s
1
.
6
ns
220
94
.
0
1
94
.
0
ns
450
)
VAC
(
T
max
OFF
µ
=
−
−
⋅
=
)
VAC
(
T
)
VAC
(
T
min
OFF
max
OFF
x =
ρ
63
.
1
s
76
.
3
s
1
.
6
x
=
µ
µ
=
ρ
R
R
R
K
0
1
+
=



Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44


Datasheet Download

Go To PDF Page


Link URL



Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link to Datasheet    |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com