MX-CFX1 ELECTRICAL SECTION 11 – 7
3) Transport Motor Drive Circuit (Y_MOT)
This circuit rotates/stops Y_MOT and controls its rotational direc-
tion and the motor current. The circuit consists of the CPU (IC6),
the D/A converter (IC13), the constant-current chopper driver IC
(IC8), and other elements.
The signals of the stepping-motor drive excitation pattern from the
CPU (IC6-Pin97, 98, 101, 102) control the motor rotation speed
and rotational direction.
The analog signal from the D/A converter (IC13-Pin6) is divided
into the constant voltage by R76 and R77. The divided voltage is
applied to IC8-Pin3,14 to set the motor current.
4) Flapper Solenoid and Registration Clutch Drive Circuit (F_SOL and R_CL)
This circuit controls the flapper solenoid operation and the registra-
tion clutch engagement.
When the signal F_SOL is "H", Q2 turns on to activate the solenoid.
Similarly, when the signal R_CL is "H", Q3 turns on to engage the
clutch.
The flapper solenoid drive signal is the PWM signal. At the begin-
ning of the solenoid activation, the signal is adjusted to set the sole-
noid at 100% duty cycle. After the plunger of the solenoid is pulled
in, the signal is adjusted to set the solenoid at 70% duty cycle in
order to reduce the temperature rise with the plunger hold.
5) Reset Circuit
The circuit transmits a reset signal to the CPU when the power is
turned on or a power brownout is detected.
The circuit includes a watchdog timer intended to the CPU system
operation diagnosis.
After the power is turned on, normally IC3-Pin8 (*RES) is "H". How-
ever, when the +5V voltage falls to 4.2V or less because of the
power turned off or any trouble, IC3-Pin8 turns "L" to reset the
CPU.
The clock signal from the CPU is transmitted to IC3-Pin3 (CK) at a
regular interval to clear the watchdog timer embedded in IC3. How-
ever, if the clock signal from the CPU disappears because of a sys-
tem trouble, IC3-Pin8 turns "L" to reset the CPU and stop the
system operation.
6)
EEPROM Circuit
This circuit consists of the data storage EEPROM and the periph-
eral circuits.
IC4 is a storage memory for the adjustment settings of the reverse
sensor (reflective sensor) and the paper width detection potentiom-
eter, and passes the data to the CPU through the four-wire serial
interface.
Once data is stored, the data is retained and not cleared even if the
power is turned off.
Not
Mounted
Horizontal
T rans port MOT
R egis tration C L
F lapper S OL
Not Mounted
