The LM3914 is a truly versatile component. Besides LEDs, only a few other components are needed to make the ‘bidirectional’ bargraph voltmeter shown here. The circuit is similar to a conventional bar ...

Isn’t it always the way? There’s a circuit right out of the textbooks, or even a chip designed to do exactly what you want — almost exactly. It’s 80% perfect for your application, and rather than ...