DIY Voltmeter: Build Your Own Card for MATLAB Plotting

[El Moriana]

Hi,

I recently got it into my head that I would like to make an analog-digital interface card for my laptop such that I can plug two wires into the card and have the the card send data on the potential difference between the two wires to my laptop via the USB port. The plan is to then have MATLAB display a running plot of this data.

This is my goal, however I am new to electronics and have absolutely no idea how to go about doing this, in terms of components (what the card would actually need to accomplish its purpose) and in terms of how to successfully interface it with MATLAB. If possible, I'd really appreciate some guidance as to how to go ahead with this. At least so I know what direction to start going in.

 

[jsgruszynski]

Hi,

I recently got it into my head that I would like to make an analog-digital interface card for my laptop such that I can plug two wires into the card and have the the card send data on the potential difference between the two wires to my laptop via the USB port. The plan is to then have MATLAB display a running plot of this data.

This is my goal, however I am new to electronics and have absolutely no idea how to go about doing this, in terms of components (what the card would actually need to accomplish its purpose) and in terms of how to successfully interface it with MATLAB. If possible, I'd really appreciate some guidance as to how to go ahead with this. At least so I know what direction to start going in.

A-to-D converters (ADC) measure voltage so that's a starting point. Most DIY folks seem to use sound cards (audio input) as their "easy to implement with the stuff on-hand" ADC. There are also commercial and hobby USB ADCs and voltmeters available but there is a trade between cheap vs. easy/accurate. Google "USB voltmeter".

Specifics of MATLAB interfacing? The simple answer: you'll most likely get to do all that yourself.

 

[AlexTheParticle]

Thanks for any help!

Hi there,

That sounds like a really interesting project! Making your own analog-digital interface card can be a challenging but rewarding experience. To start, you will need to have a basic understanding of electronics and how circuits work. There are many online resources and tutorials available to help you learn the basics.

In terms of components, you will need an analog-to-digital converter (ADC) to convert the analog signal from your wires into digital data that can be read by your laptop. You will also need a microcontroller or FPGA to control the ADC and handle the communication with your laptop. Additionally, you will need some basic electronic components such as resistors, capacitors, and wires to build the circuit.

As for interfacing with MATLAB, you can use a serial communication protocol such as UART to send the data from your microcontroller to your laptop. You can then use MATLAB's serial communication functions to read and plot the data in real-time.

I would suggest starting by researching and learning about the components and circuits you will need for your project. Once you have a better understanding of the basics, you can start designing and building your analog-digital interface card. Good luck with your project!