Close
0%
0%

Small OLED panel meter

DIY customizable 0.96'' display voltmeter, ammeter combo

marius-taciucMarius Taciuc
Following
Liked Like project

Just one more thing

To make the experience fit your profile, pick a username and tell us what interests you.

Pick an awesome username
hackaday.io/
Your profile's URL: hackaday.io/username. Max 25 alphanumeric characters.
Pick a few interests
Projects that share your interests
People that share your interests

We found and based on your interests.

Choose more interests.

OK, I'm done! Skip
Similar projects worth following
885 views
0 comments
5 followers
View Gallery
In 2017 I created this custom made panel meter from scratch.
https://hackaday.io/project/27794-build-your-own-panel-meter
Now I wanted to improve this design and thought of coming up with a new version that use the fancy 0.96'' OLED display. This design also has the merit of being smaller and nicer from many other points of view.

This design operates based on the LM324 OpAmp from Texas Instruments and I explain both the functionality of the schematic and how the gain of the amplifier works in the following video:

After I finished with this project, I begin to feel very nice about it and to really start to enjoy it. I believe it will serve me well in the future and I can only imagine that I am goin to incorporate it into different future creations. 

This time, for this project I decided to do something that might help many beginners out there. That is trying to explain how I created the schematic and my entire thought process that I put behind it. 

I managed to insert everything into a 3D printed case and the newly installed panel meter looks nicely on my power supply. 

The case *.stl files can be downloaded from here: 

https://cults3d.com/en/3d-model/various/case-files-for-the-small-oled-panel-meter-project

Pannel meter OLED version 2021.dch

schematic - to be opened with DipTrace

dch - 226.99 kB - 02/27/2021 at 15:26

Download

Pannel meter OLED version 2021.dip

Layout - To be opened with DipTrace

dip - 251.74 kB - 02/27/2021 at 15:26

Download

Pannel meter OLED Marius Taciuc Feb2021.zip

Complete set of gerber files which I used to order the actual PCBs

x-zip-compressed - 23.60 kB - 02/27/2021 at 15:26

Download

Panel meter OLED 2021 firmware backup 1_1.txt

Firmware

plain - 26.08 kB - 02/27/2021 at 15:26

Download

  • Warnings and precautions

    Marius Taciuc • 03/18/2021 at 17:54 • 0 comments

    This project could present some potential dangers if it is not handled properly. 

    - Short circuits or currents that are higher than 10A on the meter could damage the equipment and/ or generate domestic fires. 

    - Negative voltages on the measuring output of the meter are not allowed. The entire board and all the electronics in it are reverse polarity protected through the D101 diode, but negative voltages on the output might damage the shunt and other components. Please check the maximum ratings chart posted in this project. 

    - This device was designed for the purpose of learning and helping others learn about these things. Do not base industrial processes on it. Do not use this for military, aero-spatial medical or automotive applications. This device was not designed or tested for these purposes.  

    - Do not connect this device at the mains. Do not even begin to imagine trying to measure AC~ 110 -240V with it. It was not designed for this. Failing to comply with this might result in electrocution, death, injuries, shop equipment damage and/or fire. 

    - The designer of this device (AKA me) assumes no responsibility for any inconvenience that might result out of misusing this design. 

  • Inputs, outputs and maximum ratings

    Marius Taciuc • 03/17/2021 at 14:31 • 0 comments

    If you watch the video, you will understand that this meter has a jumper trace on the board and this allows it to be connected in two ways. If the jumper is present, the meter will be powered from the measured voltage. This automatically means that it will only measure voltages from 6V to 35V. If the user wants to disconnect the meter power from the measured power, that can be done by removing this link right here:

    You have to simply scrape off this trace or a length of 2mm out of it and interrupt its continuity. You can then solder an input power wire to the input terminal of the D101 diode on the other side of the board. This new wire will be the separate power input for the meter. In this way, the meter will measure voltages from 0 to 35V present on the J300 connector. 

    As for the maximum ratings this meter would be able to measure the followings:

View all 2 project logs

  • 1
    Ordering PCBs

    I ordered my PCBs from PCBway.com

    If you want to replicate this project, just send them the provided gerber files and they can send you the PCBs through mail anywhere in the world. I've been working with them for a long time now and they proved to be very reliable and trustworthy. 

  • 2
    How to calibrate

    Find this section in the firmware:

    It basically helps if your sw declared values of the components are matching the real values. So aside from the fact that I recommend using 1% components for the voltage divider and the OpAmp resistors, please take the most precise multimeter that you have laying around and measure the actual values of the components. 

    1) Measure and declare the proper value of R303. It must be 10K, but you can declare the actual value here.

    2) Measure and declare the real value of R302.

    3) Measure and declare the input voltage of the MCU. It should be around 3.3, but in reality you could find it to be 3.2 or 3.42. Write down the real value here.

    4) Measure and declare the R316 here. 

    5) Measure and declare the R317 here. 

    6) Finally compare the actual readings of your panel meter with a lab calibrated industrial multimeter. Write down the error. Then you can subtract the error here. Adjusting these constants will translate the measurements in the f(t) axis of the graph.  

  • 3
    How to flash it

    Like most of my MSP430 microcontroller projects, this one flashes in the same manner. Probably the most explicative sheet is the "added firmware" log inside the "Cookie Jar clock of passion" project. 

    https://hackaday.io/project/175830/logs

    I use the MSP430 LaunchPad as you can see in this link. For all of my projects I used IAR Embedded Workbench as the programming environment. 

View all 3 instructions

Enjoy this project?

Share

Discussions

Similar Projects

This project is to build experimental, safe and insulated AC power source for Power Electronics projects.
Project Owner Contributor

Building Experimental Insulated AC Power Supply

victor-jooVictor Joo

An automated lab power supply power with no mains power interface.
Project Owner Contributor

OpenSourcePowerSupply

ashley-robinsonAshley Robinson

This clock displays the time and day of the week directly from a GPS receiver.
Project Owner Contributor

GPS Driven Clock

bharbourBharbour

Project includes detailed schematics, Altium PCB files and schematics of the build.
Project Owner Contributor

13.56MHz Wireless Powered Drone

alireza-dayerizadehAlireza Dayerizadeh

Does this project spark your interest?

Become a member to follow this project and never miss any updates

Going up?

About Us Contact Hackaday.io Give Feedback Terms of Use Privacy Policy Hackaday API

© 2024 Hackaday

Yes, delete it Cancel

Report project as inappropriate

You are about to report the project "Small OLED panel meter", please tell us the reason.

Send message

Your application has been submitted.

Remove Member

Are you sure you want to remove yourself as a member for this project?

Project owner will be notified upon removal.