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KX-MB2110RUW/ KX-MB2130RUW/ KX-MB2170RUW/ KX-MB2117RUB/ KX-MB2137RUB/ KX-MB2177RUB
6.7.2.2.
O.C.P. (Over Current Protection) circuit
1. Function
If motor driver can supply more than 15 watts, FB and ADF motors may become fire hazards.
To prevent the risk of fire, this circuit is provided.
To prevent the risk of fire, this circuit is provided.
2. Circuit diagram
3. Circuit explanation
When the current supplied from 24V exceeds 0.44A, the voltage between two registers R607 and R608 becomes more than
0.6V (=0.44Ax2.7ohm/2), consequently both Q600, Q601 and Q602 turn on, then "ENABLE" signal (IC600, IC700_pin31)
becomes "Low" level.
When "ENABLE" signal becomes "High" level, FB motor drive block of IC600 is deactivated and currents of FB motor are cut
off.
So the currents which IC600 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.
0.6V (=0.44Ax2.7ohm/2), consequently both Q600, Q601 and Q602 turn on, then "ENABLE" signal (IC600, IC700_pin31)
becomes "Low" level.
When "ENABLE" signal becomes "High" level, FB motor drive block of IC600 is deactivated and currents of FB motor are cut
off.
So the currents which IC600 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.
This signal is designed to become "High" when software can not control motors properly by some accidents.
When base of Q602 becomes "High", "ENABLE" signal becomes "Low" and FB motor currents are cut off.
Therefore even in the case of software can not control motors, FB motor stops automatically for securing safety.
ADF motor currents are also cut off by the same method.
When base of Q602 becomes "High", "ENABLE" signal becomes "Low" and FB motor currents are cut off.
Therefore even in the case of software can not control motors, FB motor stops automatically for securing safety.
ADF motor currents are also cut off by the same method.
6.7.2.3.
Motor driver
Motor driver IC600 and IC700 can drive motors up to 0.8A/phase and support up to W1-2 phase excitation.
When "ENABLE" signal (IC600 and IC700_pin31) becomes "L", motor driver is activated.
Stepping pulses are output from IC300 pins A21, A22, B21, B22, B23 and C22.
Frequency and pattern of these pulses determine the motor rotation speed and excitation mode respectively.
Corresponding to these pulses, current are supplied from IC600(IC700)_pin3, pin7, pin9 and pin13 to each motor coils.
When "ENABLE" signal (IC600 and IC700_pin31) becomes "L", motor driver is activated.
Stepping pulses are output from IC300 pins A21, A22, B21, B22, B23 and C22.
Frequency and pattern of these pulses determine the motor rotation speed and excitation mode respectively.
Corresponding to these pulses, current are supplied from IC600(IC700)_pin3, pin7, pin9 and pin13 to each motor coils.
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