Service manual

EPSON Stylus Color 400 Service Manual
Rev.A
2-2
2
Timer Data: The timer IC that uses lithium battery as power source monitors how long
the power is off. When the power is turned on, it is changed to appropriate
cleaning level according to the time that the power is off.
Serial Data: The gate array receives serial data through the transceiver IC.
Parallel I/F control: With the use of IEEE1284 Nibble mode, it became possible not only to
receive the data from the host but also to return various information which
the printer possesses to the host.
[Common Driver IC]
The trapezoidal wave form circuit for head drive is became to HIC from the previous discreate structure.
Because of this, it is not necessary to adjust the adjustable VR on the board during production process.
Various electric charge/discharge control signals are all processed in the HIC.
[CR/PF Motor Drive Circuit]
Constant current drive is performed by the HIC. Out of this, only CR Motor is controlled for Micro-Step
control and HIC becomes possible to flow the appropriate current value at each steps. (PF Motor has
only 1-2, 2-2phase drive method). Also, bipolar drive is performed on the 4 cables individually. Following
pages explain each major control circuit.