Canon multipass c3000 Service Manual (en)

5.2 BJ Head Driver Block Diagram
• 128/136 bit shift resistor
Stores the printing data (HDATA) transferred from the control board at HCLOCK’s timing.
• 128/136 bit latch
Latches the printing data (HDATA) converted by the 128/136 bit shift resistor.
• Block enable decoder
After the BENB (Block enable) 0, 1, and 2 code signals are input, the specified heat timing
signal is output.  The heat timing signal is divided into eighth.
• Heater (1 to 128 and 1 to 136)
The heater generates the bubbles required for the nozzles to eject the ink.  The heater heats
the bubble jet nozzles.  Heating is executed with the timing signal produced by the block
enable decoder and the even nozzle heat enable (EvenENB), odd nozzle heat enable
(OddENB), and heat enable (HENB0 to 3) signals.
• Sub heater
This heater maintains the optimum conditions in the nozzle for ejecting ink.
• Temperature control heater
This heater controls the head temperature to stabilize the ink ejecting amount.
• Rank resistor
To execute optimum heat control of each BJ cartridge, production-related deviation in
heater characteristics is classified into 13 types which are identified by changing the rank
resistance.  From the printer MPU’s analog port, the printer MPU detects the different
rank resistance as voltage values and converts them from analog to digital for detection.
The heater’s characteristics are thereby recognized.
• Head temperature sensor
Temperature changes in the nozzle’s heater are detected by the diode to prevent the bubble
jet head from overheating.
• Cartridge ID
With the ID0 and ID1 combinations, the BJ cartridge type (color or black or photo) is
Chapter 2: Technical Reference