It is a pretty common first project to use an Arduino (or similar) to blink an LED. Which, of course, brings taunts of: you could have used a 555! You can, of course, also use any sort of oscillator, ...

LED technology is opening thedoor to a variety of high-power-illumination applications. The circuit in Figure 1 can let you know when ac power is available. To drive a power LED from the ac line ...

CMOS relaxation oscillators have emerged as a pivotal technology in modern integrated circuits, offering a balance between low power consumption and simplicity of design. These oscillators utilise the ...