Printhead Driver Circuit - Epson Stylus COLOR 900 Service Manual

EPSON Stylus COLOR 900/900N
Table 2-14 shows the excitation modes used for the pump/ASF motor.
Table 2-14. Pump/ASF Motor Excitation Modes
Excitation mode 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
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)

2.3.8 Printhead Driver Circuit

The printhead driver circuit consists of two circuits: the common voltage
production circuit (which produces the trapezoidal waveform that drives
the PZTs) and the nozzle selector (which determines the specific PZTs
to be actuated by the trapezoidal waveform). The common voltage
production circuit is located on the C265 main board and the nozzle
selector is located in the printhead. See
diagram showing the printhead driver components located on the main
board.
The pre-driver ICs (CXA2128: IC15 and 16) produce the trapezoid
waveform and transistors Q3 - Q6 amplify it. Unlike previous products,
serial data is transferred to each nozzle row independently to reduce
the data latch time required to form one dot.
Chapter 2 Operating Principles
Figure 2-20 for the block
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