In this post, two LED blinking circuits are given below. First one is dancing bi-color LEDs (two different color LEDs) where the two color LED will run in sequence. In the second circuit, we will ...

Lighting a string of LEDs at a constant brightness requires driving it with a regulated current. A boost converter is commonly used to step up the voltage to a level high enough to bias the LEDs on ...

In a previous article, I discussed LEDs in general and their properties. In this write-up, I want to give some examples of driving LEDs and comparing a few of the most commonly used methods. There is ...

The Design Idea in Figure 1 indicates a low-battery condition in an audio test instrument that is powered by four AA cells. As the instrument was otherwise an all-discrete design, this same approach ...

I needed a simple LED indicator showing that a particular voltage level had been reached—specifically, that a capacitor had charged to a particular potential. I was convinced that there must be a way ...

This idea describes a white- LED (WLED) driver circuit controlled by a simple ambient light sensor (ALS). A typical application would be a brightness control for cell-phone backlighting. On a very ...

[Henryk] just sent us his latest episode of simple LED circuit puzzles. In front of the camera he solders one pin of each of the 3 LEDs to a different switch. He then puts the three assemblies in his ...