Samsung BD-E8900 - Power; About S.M.P.S (Ringing Choke Converter Method); Circuit Descripcotion [FLY-Back RCC(Ringing Choke Converter)] Control

6.SchematicDiagrams
6.2.Power
6.2.1.AboutS.M.P .S(RingingChokeConverterMethod)
Terms
1)1st:Commonpowerinputto1stwinding.
2)2nd:Circuitfollowingsoutputwindingoftransformer.
3)f(Frequency):Switchingfrequency(T:Switchingcycle)
4)Duty:(Ton/T)x100
6.2.2.Circuitdescripcotion[FLY-BackRCC(RingingChokeConverter)]Control
1)ACPowerRectication/SmoothingTerminal
a)BD01~04:ConvertACpowertoDC(Waverectication).
b)C1S05B:SmooththevoltageconvertedtoDC.
c)L1S01,C1S03,C1S04:Noiseremovalatpowerinput/output.
d)R1S02:Rushcurrentlimitresistanceatthemomentofpowercordinsertion.
WithoutP1S02,thebridgediodemightbedamagedastherushcurrentincreases.
2)SNUBBERCircuit:D1S10,C1S10,R1S10
a)Preventresidualhighvoltageattheterminalsofswitchduringswitchoff/Suppressnoise.Highinvertedpoweroccursatswitchoff,becauseofthe1stwindingoftransformer:(V=-L1xdi/dt.L1:LeakageInduction)Averyhighresidualvoltageexistonboth
terminalsofIC1becausedtisaveryshort.
b)SNUBBERcircuitprotectsIC1fromdamagethroughleakagevoltagesuppressionbyRC,(ChargestheleakagevoltagetoDIS10andCIS10anddischargestoR1S10).
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