STTH3BCF060 datasheet(5/8 Pages) STMICROELECTRONICS

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STTH3BCF060

Application information

Doc ID 17524 Rev 2

5/8

Application information

Figure 13.

Application schematic

2.1

BC2 topology description (ST patent)

No hard switching occurs at turn-on with BC2 topology. Inductor L in series with the power

MOS Q configuration suppresses the switch-on losses. Added winding, coupled with the

main boost inductor Lmain, in series with the STTH3BCF060 freewheel diode brings back

both recovery current from the STTH8BC065 and damping current towards the power

circuit. Another added winding in series with STTH8BC065 boost diode discharges the

nominal current stored in inductor L flowing through STTH8BC060 diode towards output

bulk capacitor.

These two added phases compared with conventional continuous mode PFC, bring back

the current corresponding to the usual switching losses in the circuit, hence BC2 (back

current circuit).

V MAINS

STTH8BC065

LMAIN

STTH8BC060

STTH3BCF060

STTH3BCF060 数据表(PDF) 5 Page - STMicroelectronics