LED-driver circuits can be dimmed by applying a variable duty cycle (pulse-width modulation, or PWM) to the LED. PWM exploits LED behavior: At higher current levels, the LED’s light output is higher ...

Find a downloadable version of this story in pdf format at the end of the story. Boost power converters have been widely used for Power Factor Correction (PFC) in ac-dc conversions [1] and for power ...

Modern power delivery systems with DSPs, FPGAs and CPUs run on lower supply voltages and consume higher current. In fact, sub-1 V voltages are everywhere now. Meanwhile, intermediate bus voltages have ...

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 ...

A few weeks ago, I saw a reader’s question about how to run PS3 cooling fans using an external electronics circuit. At the time I was busy with some other projects. The other day, I decided to put my ...

Withclosed loop speed control, the fan controller ensures that the fan isrunning at the desired speed by measuring the actual speed and adjustingthe duty cycle accordingly. Here the host specifies the ...