Motor de Búsqueda de Datasheet de Componentes Electrónicos
  Spanish  ▼
ALLDATASHEET.ES

X  

SB340 Datasheet(PDF) 5 Page - Fairchild Semiconductor

No. de pieza SB340
Descripción Electrónicos  Power Switch (FPS?? FSL1x7 to Low- Power Supplies
Download  12 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Fabricante Electrónico  FAIRCHILD [Fairchild Semiconductor]
Página de inicio  http://www.fairchildsemi.com
Logo FAIRCHILD - Fairchild Semiconductor

SB340 Datasheet(HTML) 5 Page - Fairchild Semiconductor

  SB340 Datasheet HTML 1Page - Fairchild Semiconductor SB340 Datasheet HTML 2Page - Fairchild Semiconductor SB340 Datasheet HTML 3Page - Fairchild Semiconductor SB340 Datasheet HTML 4Page - Fairchild Semiconductor SB340 Datasheet HTML 5Page - Fairchild Semiconductor SB340 Datasheet HTML 6Page - Fairchild Semiconductor SB340 Datasheet HTML 7Page - Fairchild Semiconductor SB340 Datasheet HTML 8Page - Fairchild Semiconductor SB340 Datasheet HTML 9Page - Fairchild Semiconductor Next Button
Zoom Inzoom in Zoom Outzoom out
 5 / 12 page
background image
AN-9719
APPLICATION NOTE
© 2010 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.0 • 11/2/10
5
Figure 9. Output Voltage Reflected to the Primary
As can be seen in Equation 5, the voltage stress across
MOSFET can be reduced by reducing VRO. However, this
increases the voltage stresses on the rectifier diodes in the
secondary side, as shown in Equation 6. Therefore, VRO
should be determined by a balance between the voltage
stresses of MOSFET and diode. Especially for low output
voltage applications, the rectifier diode forward-voltage
drop is a dominant factor determining the power supply
efficiency. Therefore, the reflected output voltage should be
determined such that rectifier diode forward voltage can be
minimized. Table 2 shows the forward-voltage drop for
Schottky diodes with different voltage rating.
The actual drain voltage and diode voltage rise above the
nominal voltage is due to the leakage inductance of the
transformer as shown in Figure 9. It is typical to set VRO
such that VDS
NOM and VDONOM are 70~80% of voltage
ratings of MOSFET and diode, respectively.
Table 2. Diode Forward-Voltage Drop for Different
Voltage Ratings (3A Schottky Diode)
Part Name
VRRM
VF
SB320
20V
0.5V
SB330
30V
SB340
40V
SB350
50V
0.74V
SB360
60V
SB380
80V
0.85V
SB3100
100V
(Design Example)
As can be seen in Table 2, it is
recommended to use rectifier diode with 100V voltage
rating to maximize efficiency. Assuming that the
nominal voltages of MOSFET and diode are less than
80% of their voltage rating, the reflected output voltage
is given as:
·
373 · 12
0.85
12
0.8 · 100
80
373 · 12
0.85
68
70.5
0.8 · 700
560
560
373
187
By determining
as 74V,
74
74
79
0.48
373
74
447
·
373 · 12
0.85
74
12
76.8
[STEP-4]
Determine
the
Transformer
Primary-Side
Inductance (LM)
The transformer primary-side inductance is determined for
the minimum input voltage and nominal-load condition.
With the DMAX from Step-3, the primary-side inductance
(LM) of the transformer is obtained as:
·
·
·
(7)
where fSW is the switching frequency and KRF is the ripple
factor at minimum input voltage and nominal load
condition, defined as shown in Figure 10.
For DCM operation, KRF = 1, and, for CCM operation, KRF
< 1. The ripple factor is closely related to the transformer
size and the RMS value of the MOSFET current. Even
though the conduction loss in the MOSFET can be reduced
by reducing the ripple factor, too small a ripple factor forces
an increase in transformer size. When designing the flyback
converter to operate in CCM, it is reasonable to set KRF =
0.25-0.5 for the universal input range and KRF = 0.4-0.8 for
the European input range.


Número de pieza similar - SB340

Fabricante ElectrónicoNo. de piezaDatasheetDescripción Electrónicos
logo
Vishay Siliconix
SB340 VISHAY-SB340 Datasheet
70Kb / 4P
   Schottky Barrier Rectifier
Revision: 19-Oct-09
logo
Pan Jit International I...
SB340 PANJIT-SB340 Datasheet
54Kb / 2P
   3 AMPERE SCHOTTKY BARRIER RECTIFIERS(VOLTAGE - 20 to 100 Volts CURRENT - 3.0 Amperes)
logo
Diotec Semiconductor
SB340 DIOTEC-SB340 Datasheet
138Kb / 2P
   Schottky Barrier Rectifier Diodes
logo
Vishay Siliconix
SB340 VISHAY-SB340 Datasheet
76Kb / 4P
   Schottky Barrier Plastic Rectifier
Revision: 13-Aug-13
logo
Fairchild Semiconductor
SB340 FAIRCHILD-SB340 Datasheet
45Kb / 3P
   Schottky Rectifiers
More results

Descripción similar - SB340

Fabricante ElectrónicoNo. de piezaDatasheetDescripción Electrónicos
logo
Fairchild Semiconductor
KA5S FAIRCHILD-KA5S_03 Datasheet
213Kb / 16P
   Power Switch(FPS)
KA1M0880D FAIRCHILD-KA1M0880D Datasheet
114Kb / 10P
   Power Switch(FPS)
KA1M0265R FAIRCHILD-KA1M0265R Datasheet
89Kb / 10P
   Fairchild Power Switch(FPS)
KA1M0680B FAIRCHILD-KA1M0680B Datasheet
144Kb / 12P
   Fairchild Power Switch(FPS)
KA5X0165RXX FAIRCHILD-KA5X0165RXX Datasheet
102Kb / 12P
   Fairchild Power Switch(FPS)
FS6X1220R FAIRCHILD-FS6X1220R Datasheet
471Kb / 16P
   Fairchild Power Switch (FPS)
FS6S0965RCB FAIRCHILD-FS6S0965RCB Datasheet
572Kb / 10P
   Fairchild Power Switch(FPS)
KA1M0880BF FAIRCHILD-KA1M0880BF Datasheet
95Kb / 10P
   Fairchild Power Switch(FPS)
KA5Q0740RT FAIRCHILD-KA5Q0740RT_04 Datasheet
292Kb / 12P
   Fairchild Power Switch(FPS)
FS8S0765RCB FAIRCHILD-FS8S0765RCB_06 Datasheet
1Mb / 19P
   Fairchild Power Switch (FPS??
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12


Datasheet Descarga

Go To PDF Page


Enlace URL




Política de Privacidad
ALLDATASHEET.ES
¿ALLDATASHEET es útil para Ud.?  [ DONATE ] 

Todo acerca de Alldatasheet   |   Publicidad   |   Contáctenos   |   Política de Privacidad   |   Intercambio de Enlaces   |   Lista de Fabricantes
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