M 13-2Partialblockdescription - Samsung HLRS078WX/XAA Service Manual

Circuit Description
13-2 Partial Block Description
13-2-1 Power Board Block Description
t
I
30mA ]
T30V_B : 0 _ 5mA J
s=mute : = 6V 0 ~ 2rnA ]
: 0~ 410A
6=0V B : 0=93 ~ 1=8A ]
12V B : 2.24~4.05A ]
STD5=0V 10.05 ~ 2=485A[
T30V A : 0 _5mA I
A : 0 _-1.77A ]
[ POWER CTL ]
1.What is SMPS?
This is an acronymfor SwitchingModePowerSupplyand this is responsible for receiving AC inputvoltage
(Linefrequency:50HZ~60HZ) a nd supplyinginsulatedDC output.
2. SMPSComponents
1) StandbyPower:A combinationof ICS801(SWITCHING IC) and TS801S(TRANS)that suppliesSTAND-BY5V for operating
the Micom.
2) Multi Power:The voltagesuppliedwhen the poweris turnedon.
It is a combination of IC801Sand T801Sthat suppliesvariousvoltagesincludingD12V,A6.5V,$14.5V,T30Vand
A65V.
3. SMPSOperation
1) SMPSSystem:UsesFly-Backtechnologyfor both standbyand multi power.
2) Operation:Fly-Backis one of the mostpopularpower-supply systemsand uses less powerthan 200Was wellas beingthe
cheapestof all multioutput SMPSsystems.
Let's havea lookat howit operates...
a. Converts AC input intoDO (HOT)(rectifiesto DS801beforesmoothingto CS801)
b. The convertedDC voltageis high,especiallycomparedto ground,so touchingit will causeelectricshock.
UseT801S(Trans)to insulatethesecondaryvoltageand take advantageof the PWM operations of T801S
and IC801Sto induceit.
c. Thesecondaryinducedvoltageis a dozen-KHZsquarewave power,which goesthroughthe smoothing
cap (CS822)to be generatedin the standby5',/.
d. Multipoweralso operatesthe sameway.
13-2 SamsungElectronics