Electrical Circuit Operating Principles; Main Features; Components Of Control Boards - Epson Stylus PhotoR280 Service Manual

EPSON Stylus Photo R280/R285/R290

2.2 Electrical Circuit Operating Principles

The electric circuits of the Stylus Photo R280/R285/R290 consist of the following
boards.
Table 2-4. Main Boards & Model Numbers
Board Name
Main Board
Power Supply Board
Panel Board

2.2.1 Main Features

The circuits support multi-common printing method that achieves high-speed printing
reducing the number of carriage movements.
Features of C691Main Board
An EEPROM and a reset circuit are mounted individually to reduce the cost.
This is achieved by removing a complex RTC circuit that is mounted on the
previous model (R260/R265/R270/R360/R380/R390). Stylus Photo R280/
R285/R290 do not need the complex RTC circuit because a backup timer is
not required for them.
Operations to reduce power consumption
The printer carries out the following operations to go into sleep mode.
Decreases the power voltage.
Shuts off photoelectric current of photo interrupter sensors.
Stops the motor drive circuit.
Stops some part of the clock in the ASIC.
De-energizes the motors.
Makes the head drive circuit go into standby state.
Chapter 2 Operating Principles
R280/R285/R290
C691MAIN
C691PSB
C691PNL
2.2 Electrical Circuit Operating Principles

2.2.2 Components of Control Boards

Table 2-5. Components of Control Boards
Board Name
Logic circuit
(SOC incorporated in the CPU core, Flash ROM (4 Mbit) x 1, SDRAM x 1,
Local SDRAM controller, Local SDRAM (64 Mbit)
SSCG circuit
Panel I/F
Regulator
System
Power saver
Oscillator circuit
Main
Power control circuit (PSC/ESAVE)
Board
Reset circuit
USB interface
EEPROM
Motor drive circuit (PF, CR)
Printhead drive circuit
Printer
CSIC/IF
Sensor circuits
Power switch read-in circuit
Panel Board
LED driving circuit
Revision B
Incorporated Components
24