Introduction This is a follow-up of a proof of concept I made two months ago. I used an Arduino based DAC (8 bit 8 resistor) and an op-amp to create a signal…
Category: Posts
How to add dead time to PWM
There are situations where you absolutely want to avoid signals overlapping one another. This is when you get introduced to the term dead-time. I will give you an example of a circuit…
Ten ways to drive a MOSFET, with examples
These are a couple of circuits that can drive a MOSFET. Each of them has their own pros and cons, so whether or not they are useful is highly dependent of what…
How to make an op-amp output PWM with duty-cycle control?
We can use a generic op-amp like the LM4562NA. We build an oscillator from the first op-amp in the IC. This produces a triangle-wave. We feed this wave into the second op-amp….
How does an op-amp work?
Op-amp is short for operational-amplifier. You can use it as a comparator, buffer a signal, or amplify a signal. These are some op-amps I have; they are the LM358 and the LM4562….
How to use the IR2110 gate driver
IR2110 capabilities
How to use the IR2125 MOSFET gate driver
The IR2125 can drive high-side loads up to 500 volts. And only a few external components are needed to use this compact MOSFET gate driver. Package The IR2125 is a 8 pin…
Creating the 8 bit 8 resistor DAC
I wanted to build an analog output for my Arduino, a DAC. The default solution is to create a R-2R network like in the picture below. This resistor network needs 17 resistors…
Explaining the resistor divider
A resistor divider creates a voltage in between the top voltage and ground. In this post I try to explain why that is. TLDR: It is a result of current going into…
How to power a circuit from high voltage – Repurpose a wall adapter
Repurpose a wall adapter Most of us have wall adapters collecting dust in a box. We can crack these open and reuse the board in it. And then we integrate this into…
How to rotate an image in C#
Rotation-matrix To rotate a pixel around an axis, we need to do some sinus and co-sinus calculation to it because, in short, rotation follows a circular path. The good part is that…
How to scale any voltage into the analogRead range of your microcontroller
You want to measure a voltage? But it’s outside the range of your microcontroller’s 0 to 3.3v or 5v? We can achieve this with resistors.
How to drive a relay from a digital pin, two solutions
The first is by using an NPN-transistor, and the second a N-channel-MOSFET. Both circuits are pretty much the same otherwise.
How to create a power limiter to get zero-on-the-meter to save taxes
If you are one of the many people exporting electricity to the grid, chances are you are familiar with the following… When you export electricity you also get to pay energy taxes…
How to create a smart switch for an electric boiler to save money
My electric water heater consumes a lot of electricity, and it does so at times when it is most expensive. This is because I have dynamic prices which change every hour and…