Moteur de recherche de fiches techniques de composants électroniques
  French  ▼
ALLDATASHEET.FR

X  

ML4802IS Fiches technique(PDF) 8 Page - Micro Linear Corporation

No de pièce ML4802IS
Description  PFC/PWM Controller Combo with Green Mode
Download  15 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Fabricant  MICRO-LINEAR [Micro Linear Corporation]
Site Internet  http://www.microlinear.com
Logo MICRO-LINEAR - Micro Linear Corporation

ML4802IS Fiches technique(HTML) 8 Page - Micro Linear Corporation

Back Button ML4802IS Datasheet HTML 4Page - Micro Linear Corporation ML4802IS Datasheet HTML 5Page - Micro Linear Corporation ML4802IS Datasheet HTML 6Page - Micro Linear Corporation ML4802IS Datasheet HTML 7Page - Micro Linear Corporation ML4802IS Datasheet HTML 8Page - Micro Linear Corporation ML4802IS Datasheet HTML 9Page - Micro Linear Corporation ML4802IS Datasheet HTML 10Page - Micro Linear Corporation ML4802IS Datasheet HTML 11Page - Micro Linear Corporation ML4802IS Datasheet HTML 12Page - Micro Linear Corporation Next Button
Zoom Inzoom in Zoom Outzoom out
 8 / 15 page
background image
ML4802
8
Datasheet
August 2000
control loop for the converter, which in turn drives a
current error amplifier and switching output driver. The
second requirement is met by using the rectified AC line
voltage to modulate the output of the voltage control
loop. Such modulation causes the current error amplifier
to command a power stage current which varies directly
with the input voltage. In order to prevent ripple which
will necessarily appear at the output of the boost circuit
(typically about 10VAC on a 385V DC level, or about
40VAC during Green Mode operation) from introducing
distortion back through the voltage error amplifier, the
bandwidth of the voltage loop is deliberately kept low. A
final refinement is to adjust the overall gain of the PFC
such to be proportional to 1/VIN2, which linearizes the
transfer function of the system as the AC input voltage
varies.
Since the boost converter topology in the ML4802 PFC is
of the current-averaging type, no slope compensation is
required.
PFC SECTION
Gain Modulator
Figure 3 shows a block diagram of the PFC section of the
ML4802. The gain modulator is the heart of the PFC, as it
is this circuit block which controls the response of the
current loop to line voltage waveform and frequency, rms
line voltage, and PFC output voltage. There are three
inputs to the gain modulator. These are:
1) A current representing the instantaneous input voltage
(amplitude and waveshape) to the PFC. The rectified
AC input sine wave is converted to a proportional
current via a resistor and is then fed into the gain
modulator at IAC. Sampling current in this way
minimizes ground noise, as is required in high power
switching power conversion environments. The gain
modulator responds linearly to this current.
2) A voltage proportional to the long-term rms AC line
voltage, derived from the rectified line voltage after
scaling and filtering. This signal is presented to the
gain modulator at VRMS. The gain modulator’s output
is inversely proportional to VRMS2 (except at unusually
low values of VRMS where special gain contouring
takes over to limit power dissipation of the circuit
components under heavy brownout conditions). The
relationship between VRMS and gain is designated as
K, and is illustrated in the Typical Performance
Characteristics.
3) The output of the voltage error amplifier, VEAO. The
gain modulator responds linearly to variations in this
voltage.
FUNCTIONAL DESCRIPTION (Continued)
Figure 3. PFC Section Block Diagram
FROM
GREEN MODE
CONTROLLER
VEAO
IEAO
OVP
PFC ILIMIT
VREF
POWER FACTOR CORRECTOR
+
-
7.5V
REFERENCE
VCC
VEA
+
IEA
+
-
PFC OUT
2.75V
-1V
1.6k
1.6k
8V
12
2.5V
-
+
15
VFB
2
IAC
4
VRMS
3
ISENSE
8
RAMP 1
7
RT/CT
14
13
1
16
PFC
OUTPUT
DRIVER
PFC
CONTROLLER
GAIN
MODULATOR
DUTY CYCLE
LIMIT
OSCILLATOR
÷2


Numéro de pièce similaire - ML4802IS

FabricantNo de pièceFiches techniqueDescription
logo
Fairchild Semiconductor
ML4802IS FAIRCHILD-ML4802IS Datasheet
285Kb / 15P
   PFC/PWM Controller Combo with Green Mode
More results

Description similaire - ML4802IS

FabricantNo de pièceFiches techniqueDescription
logo
Fairchild Semiconductor
ML4802 FAIRCHILD-ML4802 Datasheet
285Kb / 15P
   PFC/PWM Controller Combo with Green Mode
logo
Champion Microelectroni...
CM6805BO CHAMP-CM6805BO Datasheet
255Kb / 15P
   10-PIN Green-Mode PFC/PWM Combo CONTROLLER
CM6805A CHAMP-CM6805A_10 Datasheet
203Kb / 15P
   10-PIN Green-Mode PFC/PWM Combo CONTROLLER
CM6805BO CHAMP-CM6805BO_10 Datasheet
203Kb / 15P
   10-PIN Green-Mode PFC/PWM Combo CONTROLLER
CM6805A CHAMP-CM6805A Datasheet
256Kb / 15P
   10-PIN Green-Mode PFC/PWM Combo CONTROLLER
logo
Fairchild Semiconductor
SG6902 FAIRCHILD-SG6902 Datasheet
856Kb / 22P
   Green-Mode PFC / Flyback-PWM Controller
logo
Champion Microelectroni...
CM6802 CHAMP-CM6802 Datasheet
338Kb / 18P
   NO BLEED RESISTOR GREEN MODE PFC/PWM CONTROLLER COMBO
logo
Fairchild Semiconductor
SG6932 FAIRCHILD-SG6932 Datasheet
696Kb / 20P
   Green-Mode PFC / Forward PWM Controller
SG6905 FAIRCHILD-SG6905 Datasheet
689Kb / 21P
   Green mode PFC/Flyback-PWM Controller
ML4805 FAIRCHILD-ML4805 Datasheet
125Kb / 13P
   Variable Feedforward PFC/PWM Controller Combo
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15


Fiches technique Télécharger

Go To PDF Page


Lien URL




Politique de confidentialité
ALLDATASHEET.FR
ALLDATASHEET vous a-t-il été utile ?  [ DONATE ] 

À propos de Alldatasheet   |   Publicité   |   Contactez-nous   |   Politique de confidentialité   |   Echange de liens   |   Fabricants
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