Tuesday, July 31, 2012
This is a 12V battery checker circuit that uses 3 LEDs that light up at their respective voltages. The red LED lights up when the battery voltage is between 8 to 10V, the orange one at voltages between 10.5V to 12V and the green one when the battery voltage is above 12.5V.
This is a tried and tested battery checker circuit using one NPN and one PNP transistor. A PCB is given along with the schematic.
Electronic Circuit is a good site for hobbyist also who would like to try DIY because it shared good circuits. If you have a personalized circuit requirement you may feel free to request it through the comment box or contact me.