This low voltage circuit can be used to monitor battery 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.
Description
R1, R3 2 1K 1/4W Resistor
R2 1 5K Pot
U1 1 LM339 Voltage comparator 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.
Source: http://www.ubmthai.com/leksoundsmf3/index.php?topic=6029.30
Related Links
More about battery check Circuit
More circuit LED Display
Circuit by IC LM339
More about buzzer circuit
LED VU Meter by LM339
Squarewave Oscillator by IC LM339
Level Detector by IC LM741
LED Voltmeter for car battery by LM324
Low Battery Voltage Indicator by IC 8211
This entry was posted on Wednesday, October 10th, 2007 at 6:14 pm and is filed under battery, meter.
