While LEDs are common in voltage detection applications, I have never seen an LED circuit that is dedicated to indicating the presence of low values of current flow. This simple LED current sensor ...

If you’re working with 3.3V or 5V circuits, it’s easy for you to throw on a power or status LED here or there. [Tom Gralewicz] has found himself in a pickle, though, often working on projects with ...

Windows: Keyboard indicator lights are only useful if you're staring at the keyboard when they turn on. If you're a touch typist, Keyboard Leds puts indicator lights and caps lock warning in the ...

This LED DC voltage indicator circuit is a voltmeter, rather than simply a battery tester. As such it may measure voltages as low as 3V. It utilizes venerable LM741 operational amplifiers applied as ...