Posts tagged ‘PWM’

An Isolated DAC Using PWM Output

Arduino‘s (ATmega328P) PWM outputs via analogWrite can be conveniently turned into analog voltage levels through the use of simple RC filters. Since the PWM outputs are not isolated, using them to drive other devices directly could be potentially dangerous. This is especially true if the target circuit uses a higher supply voltage. Continue reading ‘An Isolated DAC Using PWM Output’ »

DDS Function Generator Build

I picked up an AD9850 DDS module on eBay an couple of weeks ago and decided to build a MCU controlled DDS function generator with it to replace my crude frequency generator I built earlier. Continue reading ‘DDS Function Generator Build’ »

Reverse Engineering the Syma S107G IR Protocol

I got a Syma S107G IR controlled helicopter for my son a while ago. This tiny remote control helicopter is a rather amazing toy. Not only its movement is very stable, but the rotor speed, forward backward movements and turning can be all proportionally controlled as well. I thought it might be interesting to take a look at its control protocol to see how things are done. And yes, I do have a video at the very end showing controlling the S107G using the reverse engineered remote control. Continue reading ‘Reverse Engineering the Syma S107G IR Protocol’ »

Simple Zener Diode Tester

In this post I will show you a simple Zenner diode tester circuit, when coupled with a PWM generator it can be used to measure the breakdown voltage of Zener diodes. Or more generically, it can be used to measure the breakdown voltages (e.g. BVceo, BVcbo) of BTJ transistors. Continue reading ‘Simple Zener Diode Tester’ »