Tutorials and Projects

Dive into the world of microcontrollers and electronics.
Discover tutorials and projects on DevXplained and inspire yourself for your own.

Diodes as Input Protection
They are a very effective protection against over voltage and reverse polarity. Let's look at how diodes can be used as input protection.
Low Voltage AC Source (Summary)
Let's look back at what we learned in this project series and talk about which solution fits which use case.
Low Voltage AC Source (Part 10)
Last time we built an AC source using a transistor H-bridge. This time, we replace the transistors with MOSFETs to improve the efficiency.
MAX3010x Pulse Oximeter Modules (Part 4)
The MAX3010x sensors can do more than just heart rate measurements. Let's do some pulse oximetry.
MAX3010x Pulse Oximeter Modules (Part 3)
Our previous approach for heart rate measurements didn't work very well. It's time for a better and more scientific algorithm.
MAX3010x Pulse Oximeter Modules (Part 2)
Now that we can acquire data with MAX3010x modules, it's time to apply our heart rate detection algorithm to it.
MAX3010x Pulse Oximeter Modules (Part 1)
It's time for some more advanced heart rate sensors. Today, we are going to take a look at the MAX3010x pulse oximeter sensor family.
Heart Rate Module (Part 3)
As promised, we are going to look at another solution for detecting heart beats. This time without using a buffer.
Heart Rate Module (Part 2)
In the last part of this tutorial, we already tried out the KY-039 module. Today, we are going to implement a proper heart rate detection.
Heart Rate Module (Part 1)
Today, we are going to look at a very simple heart rate sensor. Let's discover how it works and how we can measure the heart rate with it.
Low Voltage AC Source (Part 9)
We built ourselves a working, but quite complex AC source. However, our solution is not the only possible one.
LM35 Temperature Sensor
The LM35 is a cheap and easy to use analog temperature sensor found in many Arduino Kits. Let's find out how to use it.
Low Voltage AC Source (Part 8)
It's time to add the finishing touches to our op amp circuit with push-pull stage. Let's improve its efficiency.
Low Voltage AC Source (Part 7)
Additionally, to amplifying our AC signal using an op amp, we are now going to use a push-pull stage to further increase the output power.
Low Voltage AC Source (Part 6)
In the last part of this project, we used an op amp to increase the current. This time we are going to increase the output voltage.
Low Voltage AC Source (Part 5)
After we learned about different ways to generate a sine wave, it is now time to speak about amplifying the output signal.
Low Voltage AC Source (Part 4)
Today, we are going to look at a third method for generating a sine wave with an Arduino: using the Arduino's PWM output as DAC.
Low Voltage AC Source (Part 3)
We already created a sine wave using a DAC. Today, we are going to try out another method: transforming a square wave into a sine wave.
Low Voltage AC Source (Part 2)
Let's move on and generate a sine wave signal for our AC source. Our first approach: using a DAC.
MCP4725 DAC Module (Part 2)
DACs are often used together with analog circuits. As an example for this we will use the MCP4725 to build a programmable current source.