Features: Two 1A peak current totem-pole output drivers
Precision buffered 5V reference (±1%)
Large oscillator amplitude for better noise immunity
Precision duty cycle limit for PWM section
Current input gain modulator improves noise immunity
Programmable Ramp Compensation circuit
Over-Voltage comparator helps prevent output"runaway"
Wide common mode range in current sense compensators for better noise immunity
Under-Voltage Lockout circuit with 6V hysteresisPinout
SpecificationsSupply Voltage (VCC) ................................................. .................................................................35V
Output Current, Source or Sink (RAMP COMP)DC ....................................................................... 1.0A
Output Energy (capacitive load per cycle) ................... ................................................................5J
Multiplier ISINE Input (ISINE) ................................... ...............................................................1.2mA
Error Amp Sink Current (GM OUT) ........................ ....................................................................10mA
Oscillator Charge Current ........................................ ..................................................................2mA
Analog Inputs (ISENSE A, EA OUT A, INV A)................................................................. 0.3V to 5.5V
Junction Temperature ............................................. ...............................................................150°C
Storage Temperature Range ..................... ..........................................................65°C to 150°C
Lead Temperature (soldering 10 sec.) ..................... .............................................................260°C
Thermal Resistance (JA)Plastic DIP or SOIC ......................................... .............................60°C/W
DescriptionThe ML4819 is a complete boost mode Power factor Controller (PFC) which also contains a PWM controller. The PFC circuit is similar to the ML4812 while the PWM controller can be used for current or voltage mode control for a second stage converter. Since the PWM and PFC circuits share the same oscillator, synchronization of the two stages is inherent. The outputs of the controller IC provide high current (>1A peak) and high slew rate to quickly charge and discharge MOSFET gates. Special care has been taken in the design of the ML4819 to increase
system noise immunity.
The PFC section of ML4819 is of the peak current sensing boost type, using a current sense transformer or current sensing MOSFETs to non-dissipatively sense switch current. This gives the system overall efficiency over average current sensing control method.
The PWM section of ML4819 includes cycle by cycle current limiting, precise duty cycle limiting for single ended converters, and slope compensation.
ML4819 Data Sheet
