Datasheet

AN3180 A 200 W ripple-free input current PFC pre-regulator
Doc ID 17273 Rev 1 19/39
6 A 200 W ripple-free input current PFC pre-regulator
Figure 13 shows the electrical schematic of the EVL6563S-ZRC200 demonstration board, a
200 W zero-ripple-current PFC pre-regulator (see BOM in
Tabl e 1 ) based on the boost
topology modified by adding the cancellation winding to the boost inductor and a capacitor,
to make a smoothing transformer to minimize the input ripple.
Ta bl e 2 lists its electrical
specifications, while
Ta ble 3 gives the details of the boost inductor.
The design of the pre-regulator is carried out exactly in the same way as for a traditional
stage. The coupled inductor, the crucial element of this application, is designed following the
previously outlined procedure.
The controller chip used is the L6563S [
5], suitable for implementing transition-mode-
controlled PFC pre-regulators up to 250-300 W. Other notable semiconductor devices used
are the STF12NM50N (a second generation MDmesh
TM
0.38 /500 V N-channel MOSFET)
and the STTH5L06 (a Turbo2 ultrafast diode, optimized for use in transition-mode PFC
stages).
A prototype of the pre-regulator has been built and evaluated on the bench. The diagrams of
Figure 14, 15 and 16 show its typical performance; Figure 17 to 22 show some significant
waveforms.