Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.COM

X  

FAN7930MX Datasheet(PDF) 14 Page - Fairchild Semiconductor

Part # FAN7930MX
Description  FAN7930 Critical Conduction Mode PFC Controller
Download  22 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  FAIRCHILD [Fairchild Semiconductor]
Direct Link  http://www.fairchildsemi.com
Logo FAIRCHILD - Fairchild Semiconductor

FAN7930MX Datasheet(HTML) 14 Page - Fairchild Semiconductor

Back Button FAN7930MX Datasheet HTML 10Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 11Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 12Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 13Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 14Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 15Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 16Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 17Page - Fairchild Semiconductor FAN7930MX Datasheet HTML 18Page - Fairchild Semiconductor Next Button
Zoom Inzoom in Zoom Outzoom out
 14 / 22 page
background image
© 2010 Fairchild Semiconductor Corporation
www.fairchildsemi.com
FAN7930 • Rev. 1.0.1
14
mho
250
μ
mho
115
μ
Figure 33.
Gain Characteristic
6. Soft-Start: When VCC touches VSTART, internal
reference voltage is increased like a stair step for 5ms.
As a result, VCOMP is also raised gradually and MOSFET
turn-on time increases smoothly. This reduces voltage
and current stress on the power switch during startup.
Figure 34.
Soft-Start Sequence
7. “Overshoot-less” Startup: Feedback control speed
of PFC is quite slow. Due to the slow response, there is
a gap between output voltage and feedback control.
That is why over-voltage protection (OVP) is critical at
the PFC controller and voltage dip caused by fast load
changes from light to heavy is diminished by a bulk
capacitor. OVP is easily triggered at startup phase.
Operation on and off by OVP at startup may cause
audible noise and can increase voltage stress at startup,
which is normally higher than in normal operation. This
operation is better when soft-start time is very long.
However, too long startup time enlarges the output
voltage building time at light load. FAN7930 has
“overshoot-less” control at startup. During startup, the
feedback loop is controlled by an internal proportional
gain controller and when the output voltage reaches the
rated value, it switches to an external compensator after
a transition time of 30ms. In short, an internal
proportional gain controller eliminates overshoot at
startup and an external conventional compensator takes
over successfully afterward.
Figure 35.
Overshoot-less Startup Control
8. THD Optimization: Total harmonic distortion (THD)
is the factor that dictates how closely input current
shape matches sinusoidal form. The turn-on time of the
PFC controller is almost constant over one AC line
period due to the extremely low feedback control
response. The turn-off time is decided by the current
decrease slope of the boost inductor made by the input
voltage and output voltage. Once inductor current
becomes zero, resonance between COSS and the boost
inductor makes oscillating waveforms at the drain pin
and auxiliary winding. By checking the auxiliary winding
voltage through the ZCD pin, the controller can check
the zero current of boost inductor. At the same time, a
minor delay time is inserted to determine the valley
position of drain voltage. The input and output voltage
difference is at its maximum at the zero cross point of
AC input voltage. The current decrease slope is steep
near the zero cross region and more negative inductor
current flows during a drain voltage valley detection
time. Such a negative inductor current cancels down the
positive current flows and input current becomes zero,
called “zero-cross distortion” in PFC.


Similar Part No. - FAN7930MX

ManufacturerPart #DatasheetDescription
logo
Fairchild Semiconductor
FAN7930 FAIRCHILD-FAN7930 Datasheet
1Mb / 22P
   Boundary Conduction Mode Power Factor Correction (PFC)
FAN7930 FAIRCHILD-FAN7930 Datasheet
1Mb / 37P
   Interleaved Dual BCM PFC Controllers
FAN7930B FAIRCHILD-FAN7930B Datasheet
944Kb / 22P
   Critical Conduction Mode PFC Controller
logo
ON Semiconductor
FAN7930B ONSEMI-FAN7930B Datasheet
1Mb / 22P
   Critical Conduction Mode PFC Controller
September-2017, Rev. 2
logo
Fairchild Semiconductor
FAN7930BM FAIRCHILD-FAN7930BM Datasheet
944Kb / 22P
   Critical Conduction Mode PFC Controller
More results

Similar Description - FAN7930MX

ManufacturerPart #DatasheetDescription
logo
Fairchild Semiconductor
AN-6961 FAIRCHILD-AN-6961 Datasheet
434Kb / 8P
   Critical Conduction Mode PFC Controller
FAN7930C FAIRCHILD-FAN7930C Datasheet
916Kb / 22P
   Critical Conduction Mode PFC Controller
FAN7930B FAIRCHILD-FAN7930B Datasheet
944Kb / 22P
   Critical Conduction Mode PFC Controller
FAN7529 FAIRCHILD-FAN7529 Datasheet
1Mb / 20P
   Critical Conduction Mode PFC Controller
FAN7529 FAIRCHILD-FAN7529_07 Datasheet
1Mb / 20P
   Critical Conduction Mode PFC Controller
FAN7530 FAIRCHILD-FAN7530_07 Datasheet
1Mb / 20P
   Critical Conduction Mode PFC Controller
logo
ON Semiconductor
FAN7930B ONSEMI-FAN7930B Datasheet
1Mb / 22P
   Critical Conduction Mode PFC Controller
September-2017, Rev. 2
logo
Alpha & Omega Semicondu...
AOZ7111 AOSMD-AOZ7111 Datasheet
912Kb / 15P
   Critical Conduction Mode PFC Controller
logo
Fairchild Semiconductor
FAN7530 FAIRCHILD-FAN7530 Datasheet
2Mb / 20P
   Critical Conduction Mode PFC Controller
logo
ON Semiconductor
FAN7930C ONSEMI-FAN7930C Datasheet
982Kb / 22P
   Critical Conduction Mode PFC Controller
December-2017, Rev. 3
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22


Datasheet Download

Go To PDF Page


Link URL




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

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