Panasonic KX-MB1500UCW / KX-MB1520UCB Service Manual ▷ View online
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KX-MB1500UCW/KX-MB1520UCB
6.6.
CIS Control Section
The scanning block of this device consists of a control circuit and a CIS (contact image sensor), and AFE(Analog Front End) include
A/D Converter.
A/D Converter.
When an original document is inserted and the start button pressed, pin A3 of IC300 goes to a low level and the transistor Q518
turns on.
This applies voltage to the CIS. The CIS is driven by each of the signals (CCDSH, CCDCLK, Resolution) output from IC300.
The original image illuminated by the LED to output an analog image signal.
The analog image signal is input to the AFE on VINP(20pin of IC503) and converted into 16-bit data by the A/D converter inside
IC503. Then this signal undergoes digital processing in order to obtain a high-quality image.
turns on.
This applies voltage to the CIS. The CIS is driven by each of the signals (CCDSH, CCDCLK, Resolution) output from IC300.
The original image illuminated by the LED to output an analog image signal.
The analog image signal is input to the AFE on VINP(20pin of IC503) and converted into 16-bit data by the A/D converter inside
IC503. Then this signal undergoes digital processing in order to obtain a high-quality image.
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KX-MB1500UCW/KX-MB1520UCB
Resolution
The CIS can change the resolution, 300 dpi mode or 600 dpi mode. If RESOLUTION signal is High level, CIS operates 600 dpi
mode.
The other case is 300 dpi mode.
The CIS can change the resolution, 300 dpi mode or 600 dpi mode. If RESOLUTION signal is High level, CIS operates 600 dpi
mode.
The other case is 300 dpi mode.
Operation
CIS Resolution
300dpi
600dpi
COPY
Photo/Text, Text
Photo
PC SCAN
~300 X 300
400 X 400~
FAX (KX-MB1520
ONLY)
-
ALL
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KX-MB1500UCW/KX-MB1520UCB
6.7.
Motor Drive Section
6.7.1.
Engine Motor Control Circuit
1. Functions
All driving forces of printer engine part are supplied by tis engine motor.
Engine motor is controlled so as to rotate at constant speed during printing and copying.
Engine motor is controlled so as to rotate at constant speed during printing and copying.
2. Block Diagram of Main motor Drive circuit
Main motor drive circuit consists of motor driver IC and Current control circuit.
In order to start the motor rotation, following 3 signals are supplied from IC300.
In order to start the motor rotation, following 3 signals are supplied from IC300.
3. Explanation of each circuit
1. Motor driver
IC600 is the constant current, Bi-polar stepping motor drive IC.
This IC can drive up to 2A/phase and support up to 2W1-2 phase excitation.
When "enable" signal (IC600_pin2) becomes "L", motor driver is activated, and motor current are supplied from
IC600_pin1, pin18, pin21 and pin22 to drive the motor coil.
Excitation type is selected by the logic level of "MS1"(IC600_pin8) and S2"(IC600_pin9).
The operation of IC600 is shown in below table corresponding to each logic level of enable, MS1, and MS2.
IC600 is the constant current, Bi-polar stepping motor drive IC.
This IC can drive up to 2A/phase and support up to 2W1-2 phase excitation.
When "enable" signal (IC600_pin2) becomes "L", motor driver is activated, and motor current are supplied from
IC600_pin1, pin18, pin21 and pin22 to drive the motor coil.
Excitation type is selected by the logic level of "MS1"(IC600_pin8) and S2"(IC600_pin9).
The operation of IC600 is shown in below table corresponding to each logic level of enable, MS1, and MS2.
After setting the above signals, clock signal is supplied from IC300_pinA12 to IC600_pin14.
Whenever clock signal is supplied, current value and direction supplied to Main motor change according to the
excitation type which is determined by above signal levels.
The clock frequency also determines the motor speed.
2. Motor current control circuit
According to the rotation speed, motor current is controlled for appropriate value.
In order to control the motor current, Ref voltage of IC600 is controlled.
When Ref voltage is high, motor current is increased, and the voltage is low, motor current is decreased.
Whenever clock signal is supplied, current value and direction supplied to Main motor change according to the
excitation type which is determined by above signal levels.
The clock frequency also determines the motor speed.
2. Motor current control circuit
According to the rotation speed, motor current is controlled for appropriate value.
In order to control the motor current, Ref voltage of IC600 is controlled.
When Ref voltage is high, motor current is increased, and the voltage is low, motor current is decreased.
For the control of Ref voltage, PWM pulse is supplied from IC300_pinB8.
PWM pulse is integrated by R615 and C610.
Consequently PWM pulse is converted to DC voltage.
When duty of PWM pulse is high, Ref voltage is increased and when duty is low, Ref voltage is decreased.
PWM pulse is integrated by R615 and C610.
Consequently PWM pulse is converted to DC voltage.
When duty of PWM pulse is high, Ref voltage is increased and when duty is low, Ref voltage is decreased.
Enable
(IC600_pin2)
MS1
(IC600_pin8)
MS2
(IC600_pin9)
Excitation type
Motor Operation
H
-
-
Disable
Motor stop
L
L
L
2 Phase Excitation
Full speed operation
L
H
L
F1-2 Excitation
Half speed operation
L
L
H
W1-2 Excitation
Not used
L
H
H
2W1-2 Excitation
Not used
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KX-MB1500UCW/KX-MB1520UCB
4. Explanation of each circuit
5. Timing chart and wave form of Main motors
1. 2-2 phase excitation (Full speed)
(1) Timing chart
(1) Timing chart
(2) Wave form
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