Panasonic KX-FT71LA-B, Service Manual

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illuminated by the LED array undergoes photoelectric conversion to output an analog image
signal (AIN). The analog image signal is input to the system LSI (IC1) on ANA1 (pin 205 of IC1)
and converted into 8-bit data by the A/D converter inside IC1. Then this signal undergoes digital
processing in order to obtain a high-quality image.
5.4.5. STEPPING MOTOR DRIVE CIRCUIT
1. Function
One individual stepping motor is used for transmission and
reception. It feeds the document or recording paper synchronized
for reading or printing.
2. Circuit Operation
During motor drive, gate array IC1 pin 153 becomes a high level,
and Q14 and Q7 go ON as a result. +24 V is supplied to the motor
coil. / Stepping pulses are output from gate array IC1, causing
driver IC7 to go ON. The motor coil is energized sequentially in 2
phase increments or 1-2 phase increments, which causes a 1-step
rotation. A 1-step rotation is 0.13mm of recording paper or
document paper. The timing chart is below.
Stepping Motor Phase Pattern
Function Mode Phase Pattern Speed
Copy Fine/Half Tone 1-2 217 pps
Super Fine 1-2 108.5 pps
FAX STD 2 217 pps
Fine/Half Tone 1-2 217 pps
Super Fine 1-2 108.5 pps
——— Paper Feed 2-2 434 pps
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