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KX-MB1536RU

2.Circuit diagram

3. Circuit explanation

When the current supplied from 24V exceeds 0.44A, the voltage between two registers R657 and R658 becomes more than
0.6V (=0.44Ax2.7ohm/2), consequently both Q650 and Q700 turn on, then "PS" signal (IC700_pin20) becomes "Low" level.
When "PS" signal becomes "Low" level, ADF motor driver IC700 is deactivated and currents of ADF motor are cut off.
So the currents which IC700 can supply are limited to less than 0.44A and the wattage is also limited to less than 10.6W
(=0.44Ax24V).
By limiting the wattage less than 15W, risk of fire hazard is eliminated.

If software can not control motor by some accidents, all signals of IC300 pins A21, B21, B22, C22, A22, and B23 become
"High" level.
When these signals becomes all "High", motor driver cut off the driving current of ADF motor.
Therefore even in the case of software can not control ADF motor, ADF motor stops automatically for securing safety.

Correspondent table of operation

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KX-MB1536RU

1. 2 Phase excitaton

2. Normal Torque 1-2 Phase excitation

3. Flat Torque 1-2 Phase excitation

4. W1-2 Phase excitation

1. 2 Phase excitation

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KX-MB1536RU

2. Normal Torque 1-2 Phase excitation

3. Flat Torque 1-2 Phase excitation

4. W1-2 Phase excitation

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KX-MB1536RU

1. Normal Torque 1-2 Phase excitation

2. Flat Torque 1-2 Phase excitation

3. W1-2 Phase excitation