Battery full charge alarm circuit
The Battery full charge alarm circuit for a general battery charger. It is simplified circuit and cheap, use one transistor BC557 and display with 2 LED. Read more
Battery indicators
All post about the battery indicators
8 Low Battery Voltage Alarm indicator circuits
Why your circuit does not work? Because the battery is run out. These low voltage indicator circuits may helpful for you. If you can know before and change a new one right now. It makes you not have to waste time when using those projects. Read more