ML4824CS1_NL Fairchild Semiconductor, ML4824CS1_NL Datasheet

ML4824CS1_NL

Manufacturer Part Number
ML4824CS1_NL
Description
Manufacturer
Fairchild Semiconductor
Datasheet

Specifications of ML4824CS1_NL

Start-up Supply Current
700uA
Switching Freq
81kHz
Operating Supply Voltage (min)
12.8V
Operating Supply Voltage (typ)
13.5V
Operating Supply Voltage (max)
14.2V
Operating Temp Range
0C to 70C
Operating Temperature Classification
Commercial
Package Type
SOIC W
Pin Count
16
Mounting
Surface Mount
Lead Free Status / RoHS Status
Compliant
Features
• Internally synchronized PFC and PWM in one IC
• Low total harmonic distortion
• Reduces ripple current in the storage capacitor between
• Average current, continuous boost leading edge PFC
• Fast transconductance error amp for voltage loop
• High efficiency trailing edge PWM can be configured for
• Average line voltage compensation with brownout
• PFC overvoltage comparator eliminates output
• Current fed gain modulator for improved noise immunity
• Overvoltage protection, UVLO, and soft start
ML4824
Power Factor Correction and PWM Controller
Combo
Block Diagram
15
2
4
3
7
8
6
5
9
the PFC and PWM sections
current mode or voltage mode operation
control
“runaway” due to load removal
I AC
V FB
V RMS
I SENSE
RAMP 1
RAMP 2
V DC
SS
DC I LIMIT
2.5V
V CC
50 A
8V
+
8V
VEA
VEAO
MODULATOR
1.25V
GAIN
16
3.5k
3.5k
+
+
IEA
IEAO
+
(-2 VERSION ONLY)
1
OSCILLATOR
+
POWER FACTOR CORRECTOR
2.5V
V FB
PULSE WIDTH MODULATOR
+
x 2
V IN OK
DUTY CYCLE
General Description
The ML4824 is a controller for power factor corrected,
switched mode power supplies. Power Factor Correction
(PFC) allows the use of smaller, lower cost bulk capacitors,
reduces power line loading and stress on the switching FETs,
and results in a power supply that fully complies with
IEC1000-2-3 specification. The ML4824 includes circuits
for the implementation of a leading edge, average current,
“boost” type power factor correction and a trailing edge,
pulse width modulator (PWM).
The device is available in two versions; the ML4824-1 (f
= f
switching frequency of the PWM allows the user to design
with smaller output components while maintaining the best
operating frequency for the PFC. An over-voltage compara-
tor shuts down the PFC section in the event of a sudden
decrease in load. The PFC section also includes peak current
limiting and input voltage brown-out protection. The PWM
section can be operated in current or voltage mode at up to
250kHz and includes a duty cycle limit to prevent trans-
former saturation.
LIMIT
PFC
2.7V
1V
–1V
) and the ML4824-2 (f
PFC I LIMIT
+
OVP
+
+
DC I LIMIT
V CCZ
V CCZ
13.5V
PWM
www.fairchildsemi.com
UVLO
= 2 x f
R
R
R
S
S
S
Q
Q
Q
Q
Q
Q
REFERENCE
PFC
REV. 1.0.6 11/7/03
7.5V
). Doubling the
13
V CC
PWM OUT
PFC OUT
V REF
PWM
14
12
11

Related parts for ML4824CS1_NL

ML4824CS1_NL Summary of contents

Page 1

ML4824 Power Factor Correction and PWM Controller Combo Features • Internally synchronized PFC and PWM in one IC • Low total harmonic distortion • Reduces ripple current in the storage capacitor between the PFC and PWM sections • Average current, ...

Page 2

ML4824 Pin Configuration Pin Description PIN NAME 1 IEAO PFC transconductance current error amplifier output 2 I PFC gain control reference input Current sense input to the PFC current limit comparator SENSE 4 V Input for PFC ...

Page 3

PRODUCT SPECIFICATION Absolute Maximum Ratings Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. Parameter V Shunt Regulator Current CC I ...

Page 4

ML4824 Electrical Characteristics Unless otherwise specified 25mA Symbol Parameter Input Bias Current Output High Voltage Output Low Voltage Source Current Sink Current Open Loop Gain Power Supply Rejection Ratio OVP Comparator Threshold Voltage Hysteresis PFC I ...

Page 5

PRODUCT SPECIFICATION Electrical Characteristics Unless otherwise specified 25mA Symbol Parameter Line Regulation Load Regulation Temperature Stability Total Variation Long Term Stability PFC Minimum Duty Cycle Maximum Duty Cycle Output Low Voltage Output High Voltage Rise/Fall Time ...

Page 6

ML4824 Typical Performance Characteristics 250 200 150 100 (V) Voltage Error Amplifier (VEA) Transconductance (g 16 IEAO VEAO V FB VEA IEA 3.5k 15 – + 2.5V + – ...

Page 7

PRODUCT SPECIFICATION Functional Description The ML4824 consists of an average current controlled, continuous boost Power Factor Corrector (PFC) front end and a synchronized Pulse Width Modulator (PWM) back end. The PWM can be used in either current or voltage mode. ...

Page 8

ML4824 3. The output of the voltage error amplifier, VEAO. The gain modulator responds linearly to variations in this voltage. The output of the gain modulator is a current signal, in the form of a full wave rectified sinusoid at ...

Page 9

PRODUCT SPECIFICATION ML4824’s voltage error amplifier has a specially shaped nonlinearity such that under steady-state operating condi- tions the transconductance of the error amplifi local minimum. Rapid perturbations in line or load conditions will cause the input ...

Page 10

ML4824 V OK Comparator IN The V OK comparator monitors the DC output of the PFC IN and inhibits the PWM if this voltage on V its nominal 2.5V. Once this voltage reaches 2.5V, which corresponds to the PFC output ...

Page 11

PRODUCT SPECIFICATION In the case of leading edge modulation, the switch is turned OFF right at the leading edge of the system clock. When the modulating ramp reaches the level of the error amplifier output voltage, the switch will be ...

Page 12

ML4824 TYPICAL APPLICATIONS Figure 6 is the application circuit for a complete 100W power factor corrected power supply, designed using the methods and general topology detailed in Application Note 33. AC INPUT 85 TO 265VAC F1 C1 3.15A 470nF 3.1mH ...

Page 13

PRODUCT SPECIFICATION Mechanical Dimensions 16 PIN 0.02 MIN (0.50 MIN) 0.055 - 0.065 (4 PLACES) (1.40 - 1.65) 0.170 MAX (4.32 MAX) 0.016 - 0.022 0.125 MIN (0.40 - 0.56) (3.18 MIN) REV. 1.0.6 11/7/03 inches (millimeters) ...

Page 14

ML4824 Mechanical Dimensions 0.400 - 0.414 (10.16 - 10.52) 16 PIN 0.024 - 0.034 0.050 BSC (0.61 - 0.86) (1.27 BSC) (4 PLACES) 0.012 - 0.020 0.090 - 0.094 (0.30 - 0.51) (2.28 - 2.39) 14 inches ...

Page 15

... NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems ...

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