Service manual
.
REV.-A
2.3.5 Paper Feed Motor Drive Circuit
{:
%
The PF motor (a stepping motor) is used to advance the paper. The minimum advance rate is 1/216 inch. The
.,,.
,
motor is a 2-2 phase, constant voltage drive motor. CPU ports
(P70
to
P73)
are used to control the PF motor.
Phase data for the PF motor are outputted through these ports.
PFA
to
PF-B
are turned on or off within the
uPA1476H
(lCl) depending on the phase data sent from the CPU.
When there is an output at A19 of the CPU, a +35 V voltage is supplied to the PFCOM terminal of the PF motor.
Otherwise, a +5 V voltage is supplied through
D1
to hold the motor.
CPU
P70
UPA1476H (lCl)
MOTOR
ASSEMBLY, PF
PFAIN
B1
cl
PFA
:
--------
‘- ‘
---
‘-‘-;
1
t
P72
H
PF&N
B2
P71
w
PFBIN
B3
P73
PF~lN
B4
-d-
r
PF-A
:
1
t
C2
1
1
1
PFB
+
‘
1
C3
1
1
1
PF-B
:
1
C4
1
I
1
L---------------
---J
‘3:V
F
<PF MOTOR>
4-ph, 48-p PM type pulse motor
R5
35W)C
*1OYO
61(2=3(2
(per phase) (at
25
“C)
I
D1
R49
Q1
A
u
+5V
Figure 2-28. Paper Feed Motor Drive Circuit
~“”’
. .
.
2-28