Epson LQ-2550 Technical Manual page 271

A.1.1.12 S1-7304
The S1-7304 is a unipolar constant current chopper type driver IC, and includes a control/drive circuit .
for a 4-phase stepper motor.
- - - - - - - - - - - - - - - - - - - -
1 2 - - - - - - - - - - - - - - - - - - - 1 9 2 0
Figure A-28. S1-7304 Pin Diagram
Figure A-29. S1-7304 Internal Circuit
o
R4
A - 2 6
6
8
6
5
7
4
3
2
Trigger
Pulse
Circuit
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