Scanner Motor Drive Circuit - Panasonic KX-MB2085CXW Service Manual

KX-MB2085CXW/KX-MB2090CXW
<Stop operation>
In order to stop the motor rotation, following 2 signals are supplied from IC300.
1. SS signal (Output pin: Pin D24/Output Signal: "L")
When this signal is inverted by transistor Q507 and becomes "H", motor recognize this signal as "stop" signal.
2. Brake signal (Output pin: Pin D26/Output Signal: "L")
When this signal is inverted by transistor Q509 and becomes "H", motor recognize this signal as "brake on" signal.
Timing Chart of Stop operation
6.7.1.1. Engine Motor Drive Circuit
6.7.2.

Scanner Motor Drive Circuit

General
Scanner motor drive circuit is consist of motor current control circuit ,FB (Flat Bed) motor driver, ADF (Auto Document Feeder:
equipped model only) motor driver and OCP (Over Current Protection) circuit.
6.7.2.1. Motor current control circuit
1. Function
According to the scan speed, motor current is controlled for appropriate value.
For example, when scan speed is low, motor has enough driving force.
So to prevent the vibration and noise during motor rotation, motor drive current should be reduced.
When scan speed is high, motor needs much driving force. so much current should be supplied.
In order to control the motor current, VREFA and VREFB voltages of IC600 is controlled.
When VREFA and VREFB voltages are high, motor currents are increased, and the voltages are low, motor currents are
reduced.
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