Samsung DVD-E360, Service Manual

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6. Schematic Diagrams
6.2. Power
6.2.1. About S.M.P.S (Ringing Choke Converter Method)
Terms
1) 1st : Common power input to 1st winding.
2) 2nd : Circuit followings output winding of transformer.
3) f (Frequency) : Switching frequency (T : Switching cycle)
4) Duty : (Ton/T) x 100
6.2.2. Circuit descripcotion [FLY-Back RCC(Ringing Choke Converter)] Control
1) AC Power Rectification/Smoothing Terminal
a) PDS01, PDS02, PDS03, PDS04 : Convert AC power to DC(Full wave rectification).
b) PEF10 : Smooth the voltage converted to DC.
c) PCD01, PCD02, PBS01 : Noise removal at power input/output.
d) PVA1 : SMPS protection at power surge input.
2) SNUBBER Circuit : PDS11, PCD12, PRS13, PCD11, PPS12
a) Prevent residual high voltage at the terminals of switch during switch off/Suppress noise. High inverted power occurs at switch (PQR11) off, because of the 1st winding of transformer : (V=-L1 xdi/dt. L1 : Leakage Induction) A very high residual voltage
exist on both terminals of PICF1 4, 5~8pin because dt is a very short.
b) SNUBBER circuit protects PQR11 from damage through leakage voltage suppression by RC, (Charges the leakage voltage to PDS11, PER13, PCD12 and discharges to PRS11, PRS12).
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