A circuit diagram is a graphical representation of an electrical circuit that employs either simple representations of parts or industry standard symbols. The use of symbols is determined by the audience that is examining the graphic. This is a simple circuit battery voltage monitor that indicates the battery status by monitoring the battery. The battery voltage monitor circuit is designed and manufactured around the op amp IC LM709 and configured as a comparator. The two-color LED is used as an indicator and indicates the power status of the three 12V batteries. When the voltage level rises above 13.5 volts, the output of IC1 goes low, as a result the LED starts to brighten and emit red light.
