Samsung RS265 LAWP Service Manual

7611. CIRCUIT DESCRIPTIONS11-1) Source Power Circuit11-2) Oscillator Circuit11-3) Reset CircuitTerminal Oscillation FrequencyXin(#30)Xout(#31)4MHz4MHzThis circuit shows SMPS(Switch Mode Power Supply) which converts AC input voltage (115V, 60Hz) to a high DC voltage(170V). The input AC source power is converted to DC through a wave rectifier (BD1) and the converted DC power willgenerate a constant waveform on the switching transformer using a high speed (100KHz) switching motion of TOP223Y.The D104 will rectify the generated voltage and transform into a steady 12V DC source power used for the digital displaypanel and relays. The regulator (KA7805) finally transforms into 5V DC source power for the control board and sensor’scircuits.Caution) Be careful to handle this circuit due to high voltages (AC115V, DC170V)This is oscillator circuit to generate synchronous clocks used to calculate the time for the microprocessor operation.Note) If the specification of resonator changes, micro-processor can not work properly.The reset circuit is to initialize the values RAM č other sectors of micro-processor. When the power is engaged initially,the reset voltage becomes “Low,” and it keeps “High” in the normal operation.Terminal VoltageVccRESETDC 5VDC 5V