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Now change the voltage of the power supply to 6.2V and adjust the VR3 until LED3 turns off. Now change the voltage of the power supply to 6.1V, and again adjust the VR2 until LED2 turns off. If you were using a 6V battery then set the voltage of the power supply to 6V. Replace the battery of the circuit with this power supply. Circuit Adjustmentsīefore using this circuit needs some tuning and requires a variable power supply.
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In this circuit, we are using a variable resistor of 10K at the input of each op-amp. This voltage is set by variable resistors.
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Each op-amp in this circuit is working as a comparator separately to monitor a specific voltage of the battery being monitored.
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