Panasonic KX-FLB852CX Service Manual page 225

7.7.3. FB (Flat Bed) MOTOR DRIVE CIRCUIT
1. Functions
This motor functions for main operations including FAX transmission, FB copy and PC scan.
This motor feeds CCD unit with synchronizing for reading.
2. Motor operation
During motor driving, pin 99 of ASIC IC604 becomes a high level, and Q54, Q55 turns ON.
As a result, +5V is supplied to pin 20 and pin 23 of IC52.
When the level of these pins become +5V enough current to drive the motor can be supplied from motor driver.
Stepping pulses are output from ASIC IC604 pins, 100 ~ 105, causing driver IC52 pins, 3, 7, 8 and 12 to drive the motor coil.
The motor coil is energized sequentially in 2 phase increments, which causes a 1-step rotation.
A 1-step rotation feeds 0.021mm of CCD unit.
7.7.3.1. TIMING CHART
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KX-FLB852CX / KX-FLB852CXS