ML4801IS ,Variable Feedforward PFC/PWM Controller ComboMarch 2001PRELIMINARYML4801Variable Feedforward PFC/PWM Controller Combo
ML4801IS ,Variable Feedforward PFC/PWM Controller Combofeatures of thiscombined PFC and PWM controller are low start-up and Low start-up current (200µ A ..
ML4803CP1 ,8-Pin PFC and PWM Controller ComboBlock Diagram7VCCPFC OFF REF VVEAO REF7V +V OVP4COMP CC+– 17.5VGNDCOMP–16.2V 235µ AM3–1M4PFC PFC OU ..
ML4803CP-1 ,8-Pin PFC and PWM Controller ComboBLOCK DIAGRAM7VCCPFC OFF REF VVEAOREF+7VV OVP4 COMPCC+–17.5VGNDCOMP–16.2V235µAM3–1M4PFC PFC OUTM1 M ..
ML4803CP2 ,Power Factor Correction (PFC) and PWM Controller ComboBlock Diagram7VCCPFC OFF REF VVEAO REF7V +V OVP4COMP CC+– 17.5VGNDCOMP–16.2V 235µ AM3–1M4PFC PFC OU ..
ML4803CP-2 ,8-Pin PFC and PWM Controller ComboFEATURESThe ML4803 is a space-saving controller for power factor Internally synchronized PFC and ..
MMBD914 ,Switching DiodesFeatures.122 (3.1)• Silicon Epitaxial Planar Diode.110 (2.8)• Fast switching diode in case SOT-23, ..
MMBD914L ,High-Speed Switching DiodeMaximum ratings are those values beyond which device damage can occur.
MMBD914LT1 ,High-Speed Switching DiodeTHERMAL CHARACTERISTICS3Characteristic Symbol Max Unit1Total Device Dissipation P 225 mWDFR−5 Board ..
MMBD914LT3 ,High-Speed Switching DiodeMaximum ratings applied to the device are individual stress limit values (notnormal operating condi ..
MMBD914-V-GS08 , Small Signal Switching Diode
MMBF0201NLT1 ,Power MOSFET 300 mAmps, 20 VoltsELECTRICAL CHARACTERISTICS (T = 25°C unless otherwise noted)ACharacteristic Symbol Min Typ Max Unit ..
ML4801CP-ML4801IP-ML4801IS
Variable Feedforward PFC/PWM Controller Combo
March 2001
PRELIMINARY
ML4801
Variable Feedforward PFC/PWM Controller Combo
GENERAL DESCRIPTIONThe ML4801 is a controller for power factor corrected,
switched mode power supplies. Key features of this
combined PFC and PWM controller are low start-up and
operating currents. 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 specifications. The ML4801 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 PFC frequency of the ML4801 is automatically set at
half that of the PWM frequency generated by the internal
oscillator. This technique allows the user to design with
smaller output components while maintaining the
optimum operating frequency for the PFC. An over-
voltage comparator 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.
FEATURES Internally synchronized PFC and PWM in one IC Low start-up current (200µA typ.) Low operating current (5.5mA typ.) Low total harmonic distortion Reduces ripple current in the storage capacitor
between the PFC and PWM sections Average current continuous boost leading edge PFC High efficiency trailing edge PWM optimized for
current mode operation Current fed gain modulator for improved noise
immunity Brown-out control, overvoltage protection, UVLO, and
soft start
BLOCK DIAGRAM
