Pf Motor Driver Circuit - Epson Stylus COLOR 1520 Service Manual

2.3.2.4 PF Motor Driver Circuit

The PF motor for this printer operates the following:
„Paper loading
„Paper feeding
„Pumping
The gate array E05B33 (IC6) outputs the phase drive control signals (PFAPH and PFBPH), phase data
(PFA0/1 and PPFB1/0) and voltage reference data (PFV) to the driver IC UDN2917EB (IC16). The driver
IC then controls the phase current based on the voltage reference data. This sequence enables the micro
step with a minimum of 1/720 inch at 2-2 phase.
Rev. A
Figure 2-23. PF Motor Driver Circuit Block Diagram
Operating Principles
2-23