Paper Feed Motor Drive Circuit - Epson STYLUS 4001968 Service Manual

Operating Principles

Paper Feed Motor Drive Circuit

2.3.2.5
The paper feed motor for this printer drives the following mechanisms:
Paper pickup mechanism
Pump mechanism
Driver IC SMA6501 (QM1) drives the paper feed motor by a constant voltage, unipolar drive
system. The CPU outputs phase control signals from ports P610 to P613 (pins 5 to 8) for the phase
switching operation. The CPU also outputs the supply voltage switching control signal from port
HOLD mode. The drive modes are shown in table below.
Table 2-7. Paper Feed Motor Drive Modes
Mode
CPU
(ICI)
12
Figure 2-18. Paper Feed Motor Drive Circuit Block Diagram
2-16
Phase Excitation
7
8 8
BP ~ CP "
0
'
12
. . . . . . .. . .
STYLUS 800 Service Manual
Drive Frequency (PPS)
800
650
PF
Motor
2
4
C2
7 2
9
3
4
D1
R4
. .
Rev. A