Canon BJC 6000 - Color Inkjet Printer Service Manual

4.3 Power Supply Unit4.3.1 Power Supply Unit Block Diagram4.3.2 Construction of Power Supply UnitThe power supply unit converts AC power line voltage into DC voltages that drivemotors, ICs, BJ cartridges, etc.a) AC adapterConverts the AC line voltage into 2 groups of DC voltages, +24 VDC, and +5 VDC.The output of +24 VDC is controlled by the output signal (HVCONT) from theprinter controller. The +24 VDC is used to drive the head, and carriage motor/paperfeed motor as HVH, and VM, respectively. Note that there is no output of HVH if thehead is at the replacement position or at home position. The +5 VDC is alwaysoutput by the adapter. Except for sensors, driver ICs, and BJ cartridges, allhardware components are active while AC power is supplied.b) DC/DC converterLocated on the control board to convert +5V to RGV5/RGV5I(+5 VDC) andRGV3/inRGV3(+3.3 VDC) and output them. RGV5/RGV5I is used as the drivepower for EEPROM and reset, and power voltages for HVDD, VIF, and VSEN. Notethat the output of power voltages of HVDD, VIF, and VSEN are controlled by printercontroller. RGV3/inRGV3 is used as power for the printer controller, MPU, DRAM,and control ROM, and as pull-up for switches.The +3.3VDC is intended to reduce power consumption when the printer is switchedoff as compared with +5 VDC.4-41BJC-6000Part 4: Technical ReferenceRGV3/inRGV3)Print Position Sensor (VSEN)Home Position Sensor (VSEN)Ink Sensor (VSEN)BJ Cartridge (HVDD)Parallel Interface (VIF)Carriage Motor (VM)Paper Feed Motor (VM)AC AdapterBJ Cartridge (HVH)HVCONT(+24VDC output control signal)+5V DC+24V DCAC100V+3V+5V DC(RGM5/RGV5I)MPU+5V DCEEPROMDC/DC ConverterPrinter ControllerControl ROMDRAMFigure 4-34 Power Supply Unit Block Diagram