Printhead Driver Circuit - Epson SEIJ98006 Service Manual

EPSON Stylus Color 900
Table 2-18 shows the excitation modes used for the pump/ASF motor
and their usage.
Table 2-18. Pump/ASF Motor Excitation Mode and Usage
Excitation phase Usage
Fast absorption
2-2 phase drive Semi-fast absorption
Fast feed
1-2 phase drive Micro absorption
W1-2 phase drive Not used
Normal absorption
2W1-2 phase drive
Normal feed
Constant drive
4W1-2 phase drive Slow feed
Slow absorption
Operating Principles
Minimum step
1/720" (0.035 mm)
1/1440" (0.018 mm)
1/2880" (0.009 mm)
1/5760" (0.004 mm)
1/11520" (0.004 mm)
Electrical Circuit Operation Principles

2.3.6 Printhead Driver Circuit

The printhead driver circuit consists of 2 circuits: the common voltage
production circuit (a trapezoid waveform production circuit) on the C265
main board and nozzle selector on the printhead. The pre-driver
CXA2128 (IC15, 16) produces trapezoid waveform and the transistors
(Q3 - Q6) output it. Unlike previous products, data (serial data) is
independently transferred to each nozzle row to enable reduction in
data latch time required to form one dot, while nozzle selection is
performed by ASIC, which sends serial data directly to the nozzle
selector on the printhead synchronizing with the clock signal. (A block
diagram and the circuit diagram for the nozzle selector are not included
in this manual.) The printhead driver circuit block diagram is shown in
Figure 2-18.
Revision C
72