Hi,
I have just calculated the current feedback loop for the LT1248 Average current mode PFC controller, for a 150W PFC.
I followed the equations on page 7 to 8 of the LT1509 datasheet. When I conform to their equations, the mains input waveform is a very poor sinusoid. Then, when I just tweak the current error amp compensation components, then I can get a great sinusoidal mains input current…however, the values I use for that are values that fail the requirements of the LT1509 datasheet calculations
Can you say whats going on with the current error amplifier compensation equations on page 7 and 8 of of he LT1509 datasheet? Why do they give compensation R and C values , which basically, do not work?
LT1509
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