EPSON Stylus Pro 9000 Revision B
Operating Principles Summary of Control Circuit Operations 52
2.4.1 Reset Circuit
The Reset-IC (IC7/BH6150F) used in the C277MAIN board has two built-in
reset circuits, each of which detects input voltage and power supply voltage
respectively as shown in the diagram on the right.
Pin 2 detects the voltage level of the head driver, using the input terminal of the
input voltage detection circuit. The voltage level to be detected is preset at
1.25V. When the preset voltage level is detected, the Pin 2 sends a reset
signal to reset the mechanism control circuit.
Pin 8 detects the voltage level of the logic power supply, using the input
terminal of the power supply voltage detection circuit. The voltage level to be
detected is preset at 4.2V. When the preset voltage level is detected, the Pin 8
sends a reset signal to reset the main logic circuits.
Figure 2-19. Reset Circuit
2.4.2 CR/PF Motor Driver Circuit
The EPSON Stylus Pro 9000 uses the DC servomotor to drive the CR and PF
motors. Therefore, the encoder is installed to detect the position, direction, and
speed of the carriage, and feedback from the encoder enables the software
servo control system to control the CR/PF motors.
The signal received from the Pin 60/61 in the IC32 enables the chopping
control system to control the output from the motor drive IC, and the output
from the Pin 10 in the motor drive IC (IC35/33) feeds back the output current
level to the IC32.
The Electro-magnetic Relay (LA1/LA2) is located on the power supply line for
the DC/PF motors, and it cuts off the power supply when the front cover is
open.
Figure 2-20. CR/PF Motor driver circuit
To Next Page
Loading...
