CHAPTER 2
2 - 2
COPYRIGHT 2003 CANON INC. CANOSCAN 9900F REV.0 FEB. 2003 PRINTED IN JAPAN (IMPRIME AU JAPON)
ASIC
USB
Controller
Regulator
Motor
Driver
FARE
Unit
Drive
Motor
CCD
PCB
Analog IC
Button PCB
+24V
AC adapter
Host Computer
Scanner Button
Power LED
DRAM
Home
Position
Sensor
Control
Program
J2
JP9
JP1
JP8
JP2
Scanning
Lamp
Inverter
PCB
J1
FAU
FAU Lamp
Inverter
PCB
JP9
IEEE-1394
Controller
JP9
JP9
B. Electrical System
1. Outline
Figure 2-2 is an electric system circuit diagram.
The scanner is not equipped with CPU. The device driver with a control program installed in
the host computer functions as CPU. The host computer sends a command to the ASIC via
the USB controller or IEEE 1394 controller. The ASIC controls the whole electrical circuits
and image processing of the scanner. The image signals read by the CCD are converted into
digital data by analog IC. The digital data is then processed by the ASIC and is output to the
host computer via USB interface.
Figure 2-2