Epson Stylus Scan 2000, Service Manual

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EPSON Stylus Scan 2000 Revision A
Operating Principles Electrical Circuit Operating Principles 50
2.5.2 B101 Main
Various DC voltage generated on the B101 PSB/PSE board is added various signals in
order to drive the printer function on the B101 Main board the drive of CR/PF (Pump)
motor and printing head is performed. The following figure shows the circuit diagram
for the Stylus Scan.
Figure 2-24.
Figure 2-25. B101 Main Board Block (old!!)
[CPU]
The 16-bit CPU which is mounted on Stylus Color 740 is running at 24Mhz. Gate array
manages most of controls and monitors. Likewise the Stylus Color, the D-RAM is
applied for RAM which is used as work area for receiving data and developing the data
and CPU manages its control such as CE, RAS/CAS controls.
[Gate Array]
E05B588 controls following functions.
o
Motor control
Each motor performs data transmission that motives Micro-Step.
o
Head voltage control
In the ink jet printers, drive voltage wave form (trapezoidal wave form) in order to
drive PZT is formed in the various shapes according to the types of the printers.
Therefore, it is necessary to form appropriate drive form for each head. Head
voltage control forms necessary wave form for each control signals and outputs
them.
o
EEPROM control
The correction value to eliminate the error of each printers at production process is
installed in the fixed address of IC. When the power is turned off, the contents set
by users is written instantly, and is red to the RAM when the power is turned on.
o
Sensor Data
The sensor detects information at the various conditions, which is necessary for
the printer operation. The gate array recognizes signals and changes over to the
next control.
o
Timer Data
The timer IC that uses lithium battery as power source monitors how long the
power is off. When the power is turned on, it is changed to appropriate cleaning
level according to the time that the power is off.
o
Serial I/F Control
The gate array receives serial data through the transceiver IC.
o
Parallel I/F control
With the use of IEEE1284 Nibble mode, it became possible not only to receive the
data from the host but also to return various information which the printer
possesses to the host.
o
USB I/F Control
The transceiver circuit which control the USB interface has been incorporated into
this gate array.
[Common Driver IC]
The trapezoidal wave form circuit for head drive is became to HIC from the previous
discrete structure. Because of this, it is not necessary to adjust the adjustable VR on the
board during production process. Various electric charge/discharge control signals are
all processed in the HIC.
P-ROM
(IC3)
D-RAM
(IC4)
D-RAM
(IC5)
M-ROM
(IC6)
C90A05
(IC1)
CN3 USB
Head
CN9 HD FFC
Q2&Q3
CR Motor
PF Motor
CN7
CN8
Motor
Driver
(IC12)
Motor
Driver
(IC13)
Motor
Driver
(IC11)
E
E
P
R
O
M
(I
C
7
)
Reset
IC
(IC9)
Timer
Counter
(IC8)
C
o
m
m
o
n
D
r
iv
er
(I
C
1
1
)
CN1 Parallel
Buffer
(IC9)
E05B588
(IC2)
CR1 Batt1
Address
Data
CN11
CN6
CN4
CN5
C209 PNL
ASF Sensor
HP Sensor
PE Sensor
Transceiver
(IC10)
CN2 Serial