Sleep and wake ................................................................................................................. 98 5 Theory of operation Basic operation ................................................................................................................................. 100 Sequence of operation ..................................................................................................... 101 Product start up sequence (turn on product) ................................................................... 103 Timing chart .....................................................................................................................
104 Scanner subsystem ......................................................................................................... 105 Mechanical structure ....................................................................................... 105 Motors and fans .............................................................................................. 106 Basic block diagram ........................................................................................ 107 Basic system configuration ............................................................................. 108 Scanner unit systems .....................................................................
108 Scan mode ..................................................................................... 109 Power supply assembly .................................................................. 109 Sleep mode .................................................................................... 110 Low-voltage power supply circuit .................................................... 111 Protective functions ........................................................................ 112 Scanner controller circuit ................................................................ 113 Flatbed operation ............................................................................................
115 Flatbed document exposure control ............................................... 115 Flatbed optical drive control ............................................................ 115 Flatbed optical unit operation ......................................................... 116 Flatbed document size detection .................................................... 117 ADF operation ................................................................................................. 119 ADF document exposure control .................................................... 119 ADF document feed control ............................................................
120 ADF document size detection ......................................................... 122 ADF feeder sensors ........................................................................ 123 ADF document skew detection ....................................................... 123 Scanned data flow ........................................................................................... 124 Copy processor ............................................................................................... 125 Scanning process control signals ................................................... 126 Typical scanning process flow ........................................................
127 Engine control system ...................................................................................................................... 128 DC controller PCA ........................................................................................................... 129 High-voltage power supply circuit .................................................................................... 130 Low-voltage power supply ............................................................................................... 132 Fuser control circuit .........................................................................................................
132 Formatter system ............................................................................................................................. 134 Formatter hardware ......................................................................................................... 134 Laser/scanner system ...................................................................................................................... 135 Image formation system ................................................................................................................... 136 vi ENWW