Outline Of Electrical Circuitry - Canon iR1600 Service Manual

CHAPTER 2 BASIC OPERATION

1.2 Outline of Electrical Circuitry

The PCBs used to control the machine's major electrical mechanisms are as follows:
1.2.1 Image Processor PCB
The image processor PCB controls the machine as a whole:
a. Drive Control Block
The drive control block uses a motor control IC and motor driver IC to control the reader
motor of the reader unit.
b. Control Panel Control Block
The control panel control block uses a control IC and serial communications of the con-
trol PCB to transmit/receive data, to receive statuses of the control buttons and originals, and
to send display signal to the control IC of the control panel PCB for indication by LEDs and
LCD.
c. Reader Control Block
The reader control block processes image data read from the CS unit, and stores the result
in the SDRAM by means of DMA (direct memory access).
d. Printer Control Block
The printer control block converts 600x600-dpi image data into print data. It then sends
the resulting print data to the printer unit in the form of image signals (VDO*, VDO) in re-
sponse to the horizontal synch signal (BDO*) coming from the printer unit.
e. Sensor Detection
The sensor checks mechanism monitors the state of the reader unit and ADF to monitor
the drive mechanism.
f. Energy Save Control Mechanism
The energy save control mechanism controls the energy save function (ESS) used to de-
crease the power consumption while the machine remains in wait state.
g. Memory Function
The SDRAM possessing 16 MB of memory (as mounted) is capable of storing image data
equivalent of as many as 100 sheets (abut 2 MB; A4; with print ratio of 4%).
The 128KB SRAM is used to store settings data (user data, service data), and is backed
up by a lithium battery (BAT1; as long as 5 years with power removed).
The image memory may be expanded by adding a 32MB RAM DIMM.
h. SEND Function
The SEND function uses a network to send image scanned by the reader unit to an exter-
nal device.
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COPYRIGHT© 2002 CANON INC. 2000 CANON iR1600/iR2000 REV.1 JAN. 2002