Epson SQ-B50/2550 Technical Manual page 104

REV.-A
2.4.1.6 Top Edge Holder Motor Drive Circuit
Figure 2-37 shows the drive circuit of the top edge holder motor. (Refer also to Locaton 2-3/J-K of the
SEIMA Board Circuit Diagram in the Appendix).
The motor is operated by common voltage switching based on the TEENB signal, and by phase switching
of transistors 011-014. In A2 - 02 of the phase switching signal board, only those phase coils which
become high receive the common voltage. The waveforms at point A and B of Figure 2-37 are shown
in Figure 2-38.
+24V +5V
OCUl2AJ
TEENB
1 4 - - - ( ]
PO
A2
t--~V\f'v-----j
I
02
Common
Voltage
Swithing
Motor
Coil
GH
Figure 2-37. Top Edge Holder Motor Drive Circuit
I I
,
I
'I
~
~ ~ ~. ~ ~
\
h
~ ~
r
-
- -
-
'"
..
-
-
1 -
-
I .....
r
1
V
1
I
h
il r1
In
rl
--,
1 1
- -,
1
50~
5V
10
me
~
Omt
Upper: 011 - 014 collectors (A waveform)
Lower: 011 - 014 Bases (B Waveform)
Figure 2-38. Operating Waveforms for the Top Edge Holder Motor Driver Circuit
2-36