Samsung HP-R5052, Service Manual

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Circuit Description
13-8 Samsung Electronics
2. Description of Each Block
- Input Filter Circuit
This consists of a Common Mode Reactor LF801, X-condenser C803, C804, Line by-pass condenser(Y con), C801, C802,
C823, C824 and a lightning conductor, Z801.
The external noise from the AC line and the feedback noise from the internal power are reduced.
- Rectification Circuit
Converts (rectifies) the supplied AC current into DC.
- MAIN SWITCHING Circuit Block
Transmits the energy of the electrolytic capacitor (C805) to the secondary coil, T801 [MAIN TRANS], by turning the MOS-FET
embedded in U802 (5M0565R) on or off for PWM power, and generates a DC output voltage of +5.3V, +6.5V, +12V and +30V.
When the input voltage is supplied, the activation voltage is supplied to Pin 3 of U802, and U802 starts oscillating.
Via the oscillation, the energy is transmitted to the secondary coil, T801.
- DC-DC Circuit Block
The circuit that converts the energy transmitted to T801 via the oscillation of the MAIN SWITCHING U802 into DC voltage.
The +6.5V and +12V voltages are controlled by the Voltage Regulator and the +30V output voltage is controlled by the Turn
Ratio of T801.