Pf Motor Driver Circuit - Epson Stylus COLOR 900 Service Manual

EPSON Stylus COLOR 900/900N

2.3.6 PF Motor Driver Circuit

The PF motor drive IC (LB1847: IC11) enables 4W1-2 phase excitation.
A stepping motor is used for the PF motor to move the carriage
accurately and also to minimize the motor's vibration during printing.
Figure 2-18
shows the PF motor driver circuit block diagram. Table
2-13 shows the excitation modes used for the PF motor.
P h a s e C R A ( B )
E N B ( p e r m i s s i o n )
s i g n a l
E 0 5 B 5 9 ( I C 2 )
1 4 0
P F I A 0
1 3 9
P h a s e A s e t t i n g
P F I A 1
c u r r e n t s i g n a l
1 3 8
P F I A 2
( 1 6 p a t t e r n s )
1 3 7
P F I A 3
1 3 3
P F I B 0
1 3 4
P h a s e B s e t t i n g
P F I B 1
c u r r e n t s i g n a l 1 3 5
P F I B 2
( 1 6 p a t t e r n s )
1 3 6
P F I B 3
1 4 2
P F P H A A
P h a s e C R A ( B )
1 2 8
s e l e c t i o n s i g n a l P F P H A B
1 4 1
P F E N B A
1 2 9
P F E N B B
1 2 4
P F C T L 0
1 2 7
P F C T L 1
M o t o r s u b
1 2 5
N . C .
P F C T L 2
c o n t r o l
P F C T L ‚ R 1 2 6
P F C T L ‚ S
1 2 3
Figure 2-18. PF Motor Driver Circuit Block Diagram
Table 2-13. PF Motor Excitation Modes
Excitation mode
2-2 phase drive Not used
Fast feed 1
1-2 phase drive Fast feed 2
Special fast feed
W1-2 phase drive Not used
2W1-2 phase drive Middle-speed feed
Normal feed
4W1-2 phase drive Micro adjust feed
Slow feed
+ 4 2 + 4 2
L B 1 8 4 7 ( I C 1 1 )
2 5
I A 1
7
2 4
O U T A
I A 2
2 3
I A 3
6
O U T - A
2 2
I A 4
1 8
I B 1
9
1 9
O U T B
I B 2
2 0
I B 3
8
2 1 O U T - B
I B 4
2 7
P H A S E 1
1 6
P H A S E 2
2 6
E N A B L E 1
1 4
1 7
V B B
E N A B L E 2
+ 5
2
V R E F 1
1 3
V R E F 2
2 8
V C C
1 5
G N D
Chapter 2 Operating Principles
Usage 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)
+ 4 2 + 4 2
C N 1 0
1
P F F A
3
P F - A
P F B
2
4
P F - B
+ 4 2
M 6 2 3 8 3 ( I C 1 7 )
3
D / A x x
54