2.3.4 CR Motor Driver Circuit
The CR motor driver circuit is shown below.
The carriage motor driver circuit controls the CR motor, using an open-loop, constant drive arrangement.
2-2 and 1-2 phases excite the motor. A 2-2 phase step is equivalent to a 1-2 phase step doubled. Ports 1 to 4
of the SLA7024M are used to change the excitation phase, depending on the selected print mode. Table 2-8
describes the motor driver modes.
Table 2-8 CR Motor Driver Modes
Speed Mode
Print Speed
(CPS)
Drive
Frequency
(PPS)
Excitation
Phase
Applications
8/3
440
5280
2-2
Super Draft
3
330
3960
2-2
Draft
8/3
293.3
3520
2-2
Super Draft and Copy
2
220
5280
1-2
Super Draft & Power down
Draft & Copy
3/2
165
3960
1-2
Draft & Power down
1
110
2640
1-2
Super draft & Copy &
Power down
Draft & Copy & Power down
LQ
3/4
82.5
1980
1-2
Bit Image & Power down
2/3
73.4
1760
1-2
LQ & Copy
1/2
52.5
1320
1-2
LQ & Power down
LQ & Copy & Power down
The SLA7024M (IC12) CR motor driver circuit detects and regulates the amount of current flowing in the
carriage motor coil. The current flowing through the coil varies, depending on the speed of the CR motor.
The CPU sets the amount of current via the Address /Data line. Signals are sent to ports 3 (RFA) and 14
(RFB) of the SLA7024M. The SLA7024M sets the coil current, depending on the CR speed.
CPU
CR A
CR-A
CR B
CR-B
Gate
Array
IN A
IN B
IN-B
6
5
17
16
IN-A
1
2
3
4
PG00
PG01
PG02
PG03
R73
R74
R75
R76
+5V
R72
C31
R68
R67
C29, 30
R71
R69, 70
RFA
RFB
RSA
RSB
GND A
GNB B
A
-A
B
-B
3
14
9
10
4
15
CRI0
CRI1
CRI2
CRI3
62
63
64
65
+35V
CRCOM
S L A7 0 2 4 M
Address
Data Line
Figure 2-35 CR Driver Circuit
LQ-2170 Service Manual
Operating Principles
Rev.A
2-25
Summary of Contents for LQ-2170
Page 1: ...EPSON TERMINAL PRINTER LQ 2170 SERVICE MANUAL EPSON 4005735 ...
Page 5: ...REVISION SHEET Revision Issued Date Revision Page Rev A December 5 1995 1st issued ...
Page 11: ...Figure 1 1 Exterior View of the LQ 2170 Product Description LQ 2170 Service Manual 1 2 Rev A ...
Page 80: ......
Page 127: ...1 Abnormal CR Operation LQ 2170 Service Manual Troubleshooting Rev A 5 5 ...
Page 141: ...LQ 2170 Service Manual Troubleshooting Rev A 5 19 ...
Page 156: ...Appendix LQ 2170 Service Manual A 10 Rev A ...
Page 158: ...Appendix LQ 2170 Service Manual A 12 Rev A ...
Page 159: ...Figure A 3 C165 PSB Board Assembly Circuit Diagram LQ 2170 Service Manual Appendix Rev A A 13 ...
Page 160: ...Appendix LQ 2170 Service Manual A 14 Rev A ...
Page 161: ...Figure A 4 C165 PSE Board Assembly Circuit Diagram LQ 2170 Service Manual Appendix Rev A A 15 ...
Page 162: ...Appendix LQ 2170 Service Manual A 16 Rev A ...
Page 167: ...Figure A 9 LQ 2170 Exploded Diagrams 2 LQ 2170 Service Manual Appendix Rev A A 21 ...
Page 168: ...Figure A 10 LQ 2170 Exploded Diagrams 3 Appendix LQ 2170 Service Manual A 22 Rev A ...
Page 169: ...Figure A 11 C S F Bin1 Exploded Diagrams 1 LQ 2170 Service Manual Appendix Rev A A 23 ...
Page 170: ...Figure A 12 C S F Bin1 Exploded Diagrams 2 Appendix LQ 2170 Service Manual A 24 Rev A ...
Page 171: ...Figure A 13 C S F Bin2 Exploded Diagrams LQ 2170 Service Manual Appendix Rev A A 25 ...
Page 172: ...Table A 15 Part No Reference Table Appendix LQ 2170 Service Manual A 26 Rev A ...
Page 173: ...Table A 15 Part No Reerence Table Continue LQ 2170 Service Manual Appendix Rev A A 27 ...
Page 174: ...Appendix LQ 2170 Service Manual A 28 Rev A ...
Page 175: ...EPSON Printed in Japan 95 12 05 S ...