EPSON Stylus Color 900 Revision C
Operating Principles Electrical Circuit Operation Principles 68
Unlike previous EPSON ink jet printers, the number of the phase
excitation input ports in the motor drive IC of this printer has increased
to 8. The previous micro step system used total of 4 phase excitation
input signals for both phases A and B. (Stylus COLOR, Stylus PRO
series, and Stylus PRO XL series are exceptional, since they transfer 4-
bit serial data from ASIC to the motor driver.) This is because the micro
stepping was controlled by the software only. On the other hand,
LB1847 enables the 4W1-2 phase excitation using the hardware and is
equipped with the necessary number of input ports (8 ports) for current
setting signals. Among these input ports, 4 ports are allocated to each
phase, A and B. Therefore, 16 types of current setting data can be
constantly sent to the driver IC. The LB1847 controls the micro stepping
system by exciting the corresponding phase based on the combinations
of the setting signals sent from the ASIC.
Table 2-16 shows the excitation modes used for the CR motor and their
usage.
Table 2-16. CR Motor Excitation Mode and Usage
Excitation mode
Usage Minimum step
2-2 phase drive LQ print mode 1/120" (0.212 mm)
1-2 phase drive Not used 1/240" (0.106 mm)
W1-2 phase drive
Sort skipping
SLQ print mode
1/480” (0.053 mm)
2W1-2 phase drive
Wiping
Capping
1/960" (0.026 mm)
4W1-2 phase drive
Moving from the
capping position
Uncapping
1/1920" (0.013 mm)
