AL6562

Document Number: DS37542 Rev. 2 - 2

9 of 16

www.diodes.com

February 2015

© Diodes Incorporated

AL6562

Application Information

Figure 2 Boost Pre-Regulator PFC

POWER FACTOR CORRECTION

AL6562 functions as a transition mode PFC IC, meaning the MOSFET turns on when inductor current reaches zero, and turns off when the

current meets desired input current reference voltage, as shown in Figure 3. A typical current waveform is depicted with envelope as shown,

with the input current following that of the input voltage, achieving good power factor.

Figure 3 Typical Waveform of Inductor Current with Fixed ON Time

From a mathematical point of view, a PF value can be defined by:

θ

θ

∞

Where

θ represents displacement factor with

 as the displacement angle between voltage and current fundamentals, and

represents

distortion respectively.