Table Of Contents - NEC DPro2070SB Service Manual

1. Circuit description ............................................................................................................................ 1-1
1.1 Power block ............................................................................................................................ 1-1
1.1.1 Outline ........................................................................................................................... 1-1
1.1.2 Rectifying circuit and higher harmonics suppression (active filter)
circuit ............................................................................................................................. 1-1
1.1.3 Sub power circuit ......................................................................................................... 1-2
1.1.4 Main power circuit ........................................................................................................ 1-2
1.1.5 Demagnetizing circuit .................................................................................................. 1-2
1.1.6 Power management circuit ......................................................................................... 1-2
1.2 Deflection processor block ................................................................................................... 1-3
1.2.1 Deflection processor (IC601) ..................................................................................... 1-3
1.2.2 Pressure-reduction type horizontal deflection power circuit (IC5C0) .................. 1-3
1.2.3 Horizontal width control circuit .................................................................................. 1-3
1.2.4 Vertical deflection circuit ............................................................................................ 1-3
1.2.4.1 Sawtooth waveform generation, vertical size/position control, and
1.2.4.2 Vertical output amplification circuit ............................................................ 1-4
1.2.5 High voltage block ....................................................................................................... 1-4
1.2.6 DBF (Dynamic Beam Focus) circuit .......................................................................... 1-5
1.3 Video block ............................................................................................................................. 1-6
1.3.1 Video signal amplifier circuit ...................................................................................... 1-6
1.3.1.1 Video clamp .................................................................................................... 1-6
1.3.1.2 Video blanking ............................................................................................... 1-6
1.3.1.3 Video mixing/amplifying ............................................................................... 1-6
1.3.1.4 Control of contrast and white balance ....................................................... 1-6
1.3.2 Cut-off control circuit ................................................................................................... 1-7
1.3.2.1 Control of brightness .................................................................................... 1-7
1.3.2.2 Control of BIAS .............................................................................................. 1-7
1.3.3 OSM (On Screen Manager) ........................................................................................ 1-7
1.3.4 2 Input change circuit .................................................................................................. 1-8
1.3.5 Sync on Green circuit .................................................................................................. 1-8
1.3.6 Asset circuit .................................................................................................................. 1-8
1.3.7 AUTO-SIZE function .................................................................................................... 1-8
1.3.8 SB MODE (Super Bright Mode) function .................................................................. 1-8
1.3.8.1 Adjustment item/operating function in selecting SB Mode ..................... 1-8
1.3.8.2 Circuit (cathode) operation in selecting SB Mode [Window pattern] .... 1-9
1.3.8.3 SB Mode setting data and control method ................................................ 1-9
1.3.9 CONSTANT BRIGHTNESS function ....................................................................... 1-10
Contents
linearity control circuit .................................................................................. 1-3
iii