Samsung PS42D51SX/XEC, Service Manual

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Circuit Description
Samsung Electronics 13-5
1. Outline (PDP 42inch/50inch SMPS)
Considering various related conditions, the switching regulator with good efficiency and allowing for its small size and light weight
was used as the power supply for PDP 42inch(Schubert)/50inch(Strauss), VS requiring high power consumption Asymmetrical Half
Bridge converter and flyback converter. To comply with the international harmonics standards and improve the power factor, active
PFC(Power Factor Correction) was used to rectify AC input into +400V DC output, which in turns used as input to the switching
regulator.
2. Input
The power supply shall be capable of supplying full rated output power over free voltage ranges that are rated 100 VAC - 240 VAC
RMS nominal. Operating voltage : 90 VAC - 264 VAC
The power supply must be able to start up under peak loading at 90V AC. The power supply shall automatically recover from AC
power loss. (Note that nominal voltages for test purposes are considered to be /- 1.0V of nominal).
STD_5V & Vpr2(3.3V) is a SELV standby voltage that is always present when AC mains voltage present.
3. Output
4. Over Voltage Protection
The over voltage sense circuitry and reference shall reside in package that are separate and distinct from the regulator control
circuitry and reference. No single point fault shall be able to cause a sustained over voltage condition on any or all outputs.
The supply shall provide latch-mode Over Voltage Protection as defined below.
5. Short Circuit and Over current Protection
An output short circuit is defined as output impedance of less than 300mohms. The power supply shall shutdown and latch off for
shorting VS DC rails to return. Shorts between main output rails and STD_5V shall not cause any damages to the power supply.
The power supply shall either shutdown and latch off until the short condition is removed, at which point the P/S shall recover.
The power supply shall be capable of withstanding a continuous short-circuit to the output without damage or over stress to the
unit (components, PCB traces,connectors,etc.) under the input conditions specified in Section 3 above. Current Protection as
defined below.
Output Name Output Voltage Output Current(Max.) Using in PDP Driving
VS +190V ~ 220V (210V) 2.0A Sustain Voltage of Drive Board
VA +60V ~ 80V (70V) 3.0A Address Voltage of Drive Board
D5.3V +5.3V 5.0A
A6.5V +6.5V 3.0A
FAN_9V +9V 0.2A
VG +15V 1.0A
D12V +12V 1.5A
A12V +5.3V 0.5A
18VAMP +18V 2.5A Amp Voltage of Audio Board
VT +33V 0.006A
STD_5V +5V 1.0A Standby for Remote Control
Parameter Min Unit
VS(210V) 250 ~ V
VA(70V) 100 ~ V
VCC(+5.3V) 6.8 ~ V
Output Over Current Limit Unit
VS(210V) 20A, Constant Current.(TBD) A
VA(70V) 10A, Constant Current.(TBD) A
Output except Vs,Va No damage (Auto Recovery or Shut down.) A