Ricoh AC205 Service Manual page 17

DETAILED DESCRIPTIONS
6. DETAILED DESCRIPTIONS ........................................................ 6-1
6.1 PRINTER COMPONENT LAYOUT ...........................................................6-1
6.1.1 FRONT VIEW ...................................................................................6-1
6.1.2 REAR VIEW .....................................................................................6-2
6.2 SYSTEM LAYOUT ....................................................................................6-3
6.2.1 PAPER FEED ...................................................................................6-3
6.2.2 TRANSFER ASSEMBLY ..................................................................6-3
6.2.3 DRIVE ASSEMBLY ..........................................................................6-3
6.2.4 FUSING ASSEMBLY........................................................................6-4
Thermostat............................................................................................6-4
Thermistor.............................................................................................6-4
Hot Roller..............................................................................................6-4
Pressure Roller .....................................................................................6-4
Safety Features ....................................................................................6-4
Safety Devices......................................................................................6-4
6.2.5 SCANNING UNIT .............................................................................6-5
CCD Module Specifications ..................................................................6-5
6.2.6 LASER SCANNING UNIT (LSU) ......................................................6-5
6.2.7 TONER CARTRIDGE .......................................................................6-6
6.2.8 NEW AIO DETECTION ....................................................................6-7
6.2.9 TONER END DETECTION...............................................................6-7
6.3 CONTROLLER ..........................................................................................6-8
6.3.1 MAIN PBA ........................................................................................6-8
6.3.2 ASIC .................................................................................................6-9
Main Function Block..............................................................................6-9
6.3.3 MEMORY .........................................................................................6-9
6.3.4 FLASH MEMORY .............................................................................6-9
6.3.5 SDRAM.............................................................................................6-9
6.3.6 BATTERY BACKUP .........................................................................6-9
6.3.7 SENSOR INPUT CIRCUIT .............................................................6-10
Paper Empty Sensor...........................................................................6-10
By-pass Tray Sensor ..........................................................................6-10
Paper Feed Sensor.............................................................................6-10
Paper Exit Sensor ...............................................................................6-10
Cover Open Sensor ............................................................................6-10
DC Fan/Solenoid Driving ....................................................................6-10
Motor Driving ......................................................................................6-10
6.4 SMPS AND HVPS ...................................................................................6-11
6.4.1 HVPS..............................................................................................6-12
Transfer High Voltage (THV+) ............................................................6-12
Charge Voltage (MHV)........................................................................6-12
Cleaning Voltage (THV-).....................................................................6-12
Developing Voltage (DEV) ..................................................................6-12
Supply Voltage (SUP) .........................................................................6-13
OPC Ground ZENER Voltage.............................................................6-13
6.4.2 SMPS(SWITCHING MODE POWER SUPPLY) .............................6-14
SM v B273