Epson Stylus Photo RX700 Series, Service Manual

Page: 43 / 202

EPSON Stylus Photo RX700 Revision A
Operating Principles Operating Principles of Electric Circuitry 43
2.3 Operating Principles of Electric Circuitry
2.3.1 Overview
The major circuit boards of Stylus Photo RX700 are as follows:
„
Main Board: C583MAIN
„
Power Supply Board: C583PSB/C583PSE
„
Panel Board: C583PNL
„
CCD Unit Board (Scanner):
2.3.2 Features
„
High-Speed SPC is realized without HUB, thanks to employment of USB 2.0
multi-end point.
„
An SOC incorporating the printer controller, scanner controller, PT controller
and CPU Super Macro is realized.
„
Only one CPU (NA85E 2S by NEC) controls the printer, scanner and PT
section.
„
Equipped with one 64-Mbit Flash ROM (with 16-bit bus width) and one 32-
Mbit Flash ROM (with 16-bit bus width).
„
Equipped with one 256-Mbit SDRAM (16-bit bus width) and one 128-Mbit
SDRAM (16-bit bus width) (two SDRAM in total) for ASIC local buses, and
one 256-Mbit SDRAM (16-bit bus width) for CPU bus.
„
Two motor driver ICs (RENESAS M63160J) are mounted, each of which
controls two DC motors and one stepping motor.
„
The band width is ensured by setting the operating frequency of the local
SDRAM of SOC at 96 MHz.
„
High-speed processing is ensured because all the processing from scanning to
binarization, Microweave, and image buffer generation is carried out inside
the SOC, without via the CPU bus.
„
Equipped with a color LCD (2.5-inch low-temperature poly-silicon TFT
liquid crystal) as a standard feature.
„
With the aid of the low-current LED, power consumption is suppressed by
executing the following actions at transition to the power save mode.
•
Lowering the supply voltage for main power
•
Cutting off the photo-electric current of the photo sensor
•
Stopping the motor drive circuit
•
Stopping the UDL clock inside the ASIC
•
Entering the CPU core low consumption mode
•
High
η
power supply circuit
•
Stopping excitation of the printer motor
•
Stopping the head drive circuit
•
Turning off the CCD scanner power supply and stopping the excitation of the
scanner motor
•
Turning off the preview monitor
Figure 2-37. Main Board
Figure 2-38. Power Supply Board