Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

AN701 Datasheet(PDF) 12 Page - Vishay Siliconix

Part No. AN701
Description  reduce the size of energy storage components
Download  19 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  VISHAY [Vishay Siliconix]
Homepage  http://www.vishay.com
Logo 

AN701 Datasheet(HTML) 12 Page - Vishay Siliconix

Zoom Inzoom in Zoom Outzoom out
 12 / 19 page
background image
AN701
Vishay Siliconix
www.vishay.com
12
Document Number: 70575
16-Jan-01
Figure 22 DC-to-DC Converter Block Diagram
C1
3.3
mF
100 V
C10
10
mF
25 V
D1
D2
L1
EF12.6
9.7
mH
+
C2
3.3
mF
100 V
VCC
SENSE
OUT
–VIN
SYNC
COSC
ROSC
SS
COMP
FB
NI
VREF
SHD
+VIN
R1, 1 W
R2, 1 W
IC1
Si9420DY
TX1
PL-25
C8
22 pF
D3
R7
390 k
R3
220
W
R4
10
W
C5
2.2
mF
25 V
C3
220 pF
C4
100 pF
R5
68 k
W
C7
100 nF
C6
100 nF
R6
R10
1 k
W
R12
1 k
W
R11
1 k
W
C12
2.2 nF
IC4
TL431
IC2
Si9114A
SHUTDOWN
SYNC
14
13
12
11
10
9
8
4
3
2
1
5
6
7
6
5
4
3
2
1
NC
1 k
W
1 k
W
47
W
TCMT1020
D5SC4M
35 T
11 T
11 T
D5SC4M
C11
10
mF
25 V
+
5 V
4 A
36–72 V
DC
D3, D4 LS4148
Since this choke must carry the full output current, the
minimum number of turns required on this core is given by:
N
min +
L
choke xIChoke
Bmax xAmin
where Bmax is the maximum flux density used, and Amin is
the minimum core area. In this case Bmax = 200 mT and
Amin = 13 mm2. Substituting in this equation yields:
N
min +
8
mHx 3 A
200 mT x 13 mm2
+ 9.2 T
In this case it was decided to wind 3 layers of 12 turns of
0.315 mm in one layer each across the bobbin. This allowed
the best fill factor of the bobbin, maximizing copper area.
The result yields a choke having a dc resistance of 22 m
W and
therefore a dc copper loss of P = I2RDC = 9 x 0.022 = 200 mW
with 3 A dc. Using a core set with an AL value of 45, a
transformer of L = Nmin2 x AL = 122 x 45 x 10-9 = 6.48mH was
calculated. Measured value was 9.73
mH: slightly higher, but
acceptable.
TRANSFORMER DESIGN
See appendix A for a design using these specifications.
PERFORMANCE RESULTS
The switching waveforms in Figure 23 show that the resonant
reset is limiting the peak voltage to 120 V, well below the
maximum rating of 200 V. Note the leading edge spike caused
mainly by the peak gate current.


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   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