Electrical Circuit Operating Principles; C301Psb/Pse Board - Epson Stylus COLOR 670 Service Manual

EPSON Stylus COLOR 670

2.2 Electrical Circuit Operating Principles

The electric circuit of the Stylus COLOR 670 consists of the following boards.
o
Main board: C301MAIN Board
o
Power supply board:

C301PSB/PSE Board

o
Panel board: C209PNL Board
This section provides operating principles of C301PSB/PSE Board and
C301MAIN Board. Refer to Figure 2-11 for the major connection of the three
boards and their roles.
C209 PNL (Stylus COLOR 670)
C301MAIN Board
3.3V Driver IC 5V Driver IC
3.3V Regulator
+5V DC
Power Off
C301 PSB/PSE
Board
Figure 2-11. Electric Circuit of Stylus COLOR 670
Operating Principles
Printer Mechanism
CR Motor
PF Motor
Head Driver Board
Several Sensors
+42V DC
Electrical Circuit Operating Principles
2.2.1 C301PSB/PSE Board
The power supply boards of Stylus COLOR 670 use a RCC (Ringing Chalk
Converter) circuit, which generates +42VDC for drive line and +5VDC for logic
line to drive the printer. The application of the output voltage is described
below.
Table 2-7. C301 PSB Board
Voltage
• Motors (CR Motor, ASF/Pump Motor, PF Motor)
+42VDC • Printhead common voltage
• Printhead nozzle selector 42V drive voltage
• C301MAIN control circuit logic
• C301MAIN IC16 3.3V generating regulator
+5VDC
• C209 PNL board
• Sensors
Stylus COLOR 670 uses the delay circuit (secondary side power switch). Use
of the secondary switch enables the circuit to keep supplying voltage to 5 V
line and 24 V line for approximately 30 seconds if the printer power is turned
off through the panel switch. Even if the printer is turned off through the
panel switch while it is in operation, the printer turns the power supply off
after performing the capping operation to prevent ink leakage or dry
printhead nozzles that may be caused when the printhead is left without
capping.
AC voltage input from AC inlet first goes through filter circuit that removes
high frequency components and is then converted to DC voltage via the
rectifier circuit and the smoothing circuit. DC voltage is then lead to the
switching circuit and FET Q1 preforms the switching operation. By the
switching operation of the primary circuit, +42VDC is generated and stabilized
at the secondary circuit. This +42VDC generated by the secondary circuit is
converted to +5VDC by the chopping regulator IC of the secondary circuit.
Revision A
Application
43