led 12 volt lead acid battery meter

In the circuit, a quad voltage comparator (LM339) functions as a simple bar graph meter to display the charge condition of a 12-volt lead-acid battery. A 5-volt reference voltage is applied to each of the positive inputs of the four comparators, while the negative inputs are connected to successive points along a voltage divider. The LEDs will light up when the voltage at the negative input surpasses the reference voltage.

The circuit utilizes the LM339, a quad comparator, which allows for the monitoring of battery voltage levels with multiple output indicators. The 12-volt lead-acid battery is monitored through a voltage divider, which scales down the battery voltage to a range suitable for comparison with the fixed 5-volt reference. This is achieved by using resistors in a series configuration, where the voltage at each tap point corresponds to a specific battery voltage level.

The output from each comparator is connected to individual Light Emitting Diodes (LEDs). When the voltage at the negative input exceeds the 5-volt reference, the comparator output goes high, turning on the corresponding LED. This configuration allows for a visual representation of the battery's state of charge, where each illuminated LED indicates a specific voltage threshold.

The design ensures that the circuit can effectively monitor the battery's charge status in real-time, providing immediate feedback on the battery's health. The use of the LM339 comparator is advantageous due to its low power consumption and ability to operate over a wide voltage range, making it suitable for battery management applications. Proper selection of resistor values in the voltage divider is crucial to ensure accurate voltage scaling and threshold detection, thereby enhancing the reliability of the bar graph meter display.In the circuit, a quad voltage comparator (LM339) is used as a simple bar graph meter to indicate the charge condition of a 12 volt, lead acid battery. A 5 volt reference voltage is connected to each of the (+) inputs of the four comparators and the (-) inputs are connected to successive points along a voltage divider.

The LEDs will illuminate when the voltage at the negative (-) input exceeds the reference voltage.. 🔗 External reference