1 - 11. Circuit description1.1 Power block1.1.1 Outline(1) The power block is compatible with 100 to 120VAC/220 to 240VAC(50/60Hz).(2) The active filter circuit is adopted to suppress the higher harmonic current and improvethe power factor.(3) The circuit that supplies the electric power to the secondary side is divided into twocircuits that are respectively called the main power and sub power.Though both main and sub circuits supply the power to the secondary side in the normaloperation mode, the power is supplied from the sub power only in the power save modesince the main power is stopped.The main power is the configuration used the flyback converter type switching control IC ofthe simulative resonant operation. Moreover, the sub power is the configuration used PRC(OFF width fix) control IC.(4) The output on the secondary side is shown in Table 1.(Refer to the power system diagram1-3 in Pages 1-3, 1-4 and 1-5.)Table 11.1.2 Rectifying circuit(1) The AC input voltage is rectified in the full wave mode with the diode bridge in D901.(2) In the higher harmonic circuit of the section 1.1.4, the AC input current becomes the sinewave form in the same phase with the AC input voltage waveform, but the interference isgiven to other peripheral devices since the noise of the switching current appears on theinput side owing to the switching waveform. Therefore, L902 and C906 are inserted tosuppress the noise that is caused by the switching current.1.1.3 Surge current suppression(1) TH901 (thermistor) suppresses the rush current that flows when the power switch is turnedON. Moreover, D933 is added to protect D902 from the rush current.Power blockMain powerside+215V+80V+15V-15V+12V+7.5V+5VP-OFF+5VH. deflection circuit, Video cut off circuitVideo circuit, DBF circuit, High voltage circuitH/V deflection circuit, etc.H/V deflection circuit, etc.Video circuit, H. deflection circuit, etc.HeaterMPU, etc.Video circuit, etc.Sub powersideOutput voltageOFFOFFOFFOFFOFFOFFONOFFWhen power saveApplication
