Panasonic KX-FM330GR Service Manual page 197

6.4.5. STEPPING MOTOR DRIVE CIRCUIT
1. Function
Two individual stepping motors are used for transmission and reception. They feed the document or recording paper
synchronized for reading or printing.
2. TX Motor
During motor driving, pin 163 of ASIC IC501 becomes a high level, driver pin 12 of IC402 becomes a low level, and Q402 turns
ON. As a result, +24V is supplied to the motor coil.
Stepping pulses are output from gate array IC501 pins, 157, 160~162, causing driver IC402 pins, 16~13 to drive the TX Motor
Coil. The motor coil is energized sequentially in 2 phase increments, which causes a 1-step rotation. A 1-steprotation feeds 0.13
mm of recording paper or document paper.
The timing chart is shown below.
Copy
FAX
Paper Feed
Stand-by
Stepping Motor Drive Mode
Function Mode
Fine
Standard
Fine or Half tone
———
———
Phase Pattern
1-2 216 pps
2-2 216 pps
1-2 216 pps
2-2 216 pps
All phases are None
currently off.
155
KX-FP320G / KX-FM330G
Speed