Low Voltage Alarm

Electronic Schematics > Security and other sensors and detectors > Low Voltage Alarm

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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

To obtain an original or a certified copy: California apostille, apostille documents.

Parts:

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

Notes:

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: 838
Print version:

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Electronic circuits > Security and other sensors and detectors > Low Voltage Alarm