Cr Motor Driver Circuit; Pf Motor Driver Circuit - Epson LQ-670 Service Manual

Chapter 2 Operating Principles

2.2.2.6 CR Motor Driver Circuit

The CR motor driver circuit of this printer consists of CPU, gate array, CR motor drive IC SLA7024M (IC3)
and CR motor. The CPU sends phase data; INA, /INA, INB and/INB from the port PGO0-3 to the CR
motor IC. The current setting is de-coded in the CRFA0-3 and CRFB0-3 of the gate array by the CPU and
is output to the CR motor drive IC. The CR motor driver IC outputs phase signals; CRA, /CRA, CRB, /CRB
to the CR motor. The CR motor is driven at open loop control uni-pola rated current type by the drive IC.
Figure 2-13.CR Motor Driver Circuit

2.2.2.7 PF Motor Driver Circuit

The PF motor driver circuit of this printer consists of CPU, gate array, PF motor drive IC(IC1, IC2) and PF
motor. The CPU sends phase data(PFPHASEA/B) to the PF motor drive IC via the gate array. Also, the
current control signals;PF10A/1A, PF10B/1B are outputs to the PF motor drive IC via gate array for
current setting. The PF motor drive IC outputs phase signals; PFA, /PFA, PFB, /PFB to the PF motor.
The CR motor is driven at open loop control bi-pola rated current type by the driver ICSLA7024M(IC3).
Also, the current is controlled by the /PFHOLD signal from the gate array when the reset is performed.
Figure 2-14.PF Motor Driver Circuit
2-16
Rev. A