STMicroelectronics 250W TRANSITION-MODE PFC PRE-REGULATOR WITH L6563S EVL6563S-250W EVL6563S-250W Data Sheet

Product codes
EVL6563S-250W
Page of 32
Test results and significant waveforms
AN3119
18/32
Doc ID 16849 Rev 2
Figure 26.
EVL6563S-250W TM PFC: startup attempt at 80 Vac-60 Hz - full load
In 
Figure 26
 
a startup tentative below the threshold is shown. As seen, at startup the RUN 
pin does not allow the PFC startup even if the Vcc has reached the turn-on threshold. PFC 
output voltage remains at the peak of the input sinewave.
In 
 and 
 the waveforms of the circuit during operation of brown-out protection are 
shown. In both cases the mains voltage was increased or decreased slowly; as seen, both 
at turn-on or turn-off there are no bouncing or starting attempts by the PFC converter.
         
         
 
CH1: PFC output voltage
 
CH2: Vcc voltage (pin #14)
 
CH3: RUN (pin #10)
 
CH4: gate drive (pin #13)
Figure 27.
EVL6563S-250W TM PFC: startup 
with slow input voltage increasing - 
full load
Figure 28.
EVL6563S-250W TM PFC: turn-off 
with slow input voltage decreasing 
- full load
         
CH1: PFC output voltage 
CH2: gate drive (pin #13)
CH3: RUN (pin #10)
CH4: PWM_stop (pin #9)
         
CH1: PFC output voltage 
CH2: gate drive (pin #13)
CH3: RUN (pin #10)
CH4: PWM_stop (pin #9)