Low Voltage Alarm

This low voltage circuit can be used to monitor batteries and other volatile sources of current for problems. The circuit sounds an alarm and lights an LED, but can be interfaced to any number of other circuits for many different uses.


Schematic for Low Voltage Alarm


Part Total Qty. Description Substitutions
R1, R3 2 1K 1/4W Resistor  
R2 1 5K Pot  
U1 1 LM339 Op Amp IC  
D1 1 1N5233B Zener Diode  
D2 1 LED  
BZ1 1 Piezo Buzzer  
MISC 1 Board, wire, socket for IC  


1. The circuit will operate from 9V to 12V.

2. Adjust R2 until the alarm goes off at the correct voltage.

Title: Low Voltage Alarm
electronic circuit
Source: www.aaroncake.net/circuits/
Published on: 2005-02-10
Reads: 820
Print version: Print version

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