Figure; Cr Motor Drive Circuit - Epson LQ-860 Technical Manual

Motor Drive
2.3.6.2 CR
Figure 2-57 shows the CR motor drive circuit. Figure 2-58 shows the CR motor drive circuit signal timing.
This circuit employs unipolar stepper motor driver IC S17300A (1A), and drives the CR motor using constant
current chopper type control. The chopper type control is performed by a separately-excited system. The +
35 V power supply voltage is applied intermittently to the CR motor coil from COMAB and COMCD so that
a mean voltage is applied to the CR motor cclil, which keeps the CR motor current constant.
. Refer to Appendix A.1.1.8 for details of the S17300A.
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Figure 2-57.

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REFERENCE
VOLTAGE
GENERATION
CIRCUIT

CR Motor Drive Circuit

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