Cheap USB Digital Voltmeter




Introduction: Cheap USB Digital Voltmeter

About: I love writing, I make video in MY UPLOADED VIDEOS channel in Youtube for my instruction, and i love making something.

Digital voltmeter+USB = USB digital Voltmeter.

If you finish make charger, power bank, or any device for charging. You need to check the output voltage to use it, if the output voltage is too high or too low? you need this tools.

This tool can measure the voltage from 3v - 30v!

This tool will protect you of damage to other devices!

  • Easy to use!
  • Easy to carry!
  • Works with any usb plugs! (Pc usb, powerbank, laptop usb, and any others)
  • Very sensitive

  • Cheap!
  • And anything!

Ok Lets make it!

Step 1: You Need

  • USB male and female
  • Cheap mini digital voltmeter
  • Solder iron
  • Hot glue gun
  • Heat shrink tubing / case
  • & creativity

Step 2: Solder It

Solder the male and female usb like image. Slowly but good! Dont make any contact to another pins

Step 3: Solder the Voltmeter

Solder the voltmeter like image.

  • Negative is right
  • Positive is left

Step 4: Join the Usb & the Voltmeter

Join the usb & the voltmeter use hot glue. Don't make any contact with usb plug & the voltmeter!!

Step 5: Add Case and Test It!

Add case to make it better and stronger! I use heat shrink tubing to make the case, but you can make the case with anything you want!

Plug in this tools into charger and test it!

Thanks for Look my works

I hope you can make it better than me!

sorry for my bad english!

please share this instructables and check my other instructables




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    15 Discussions


    2 years ago

    Balsuryana, thank you for posting this design. I want to use your design idea to add a Voltmeter to a USB extension cable. I would be adding lengths of wire in between the USB ports instead of soldering them directly to each other. Thanks for the inspiration.

    1 reply

    you're welcome. btw thanks for look my works

    Terrible design and work. The solderings could short out any second.

    3 replies

    i believe you can make it better than me :) thanks for look my works

    I love this ur amazing! u made my day love homemade tech I'm geeking out again lol?

    nope, but you can connect your usb device like usb chargers or anything

    good idea but i don't understand, what doesdigital voltmeter shows?

    1 reply

    to show the voltage of the usb. btw thanks for look my works


    2 years ago

    I totally understand what you were trying to design and there is nothing wrong with your design. You basically paralleled a digital readout monitor on the VCC and GND pins of the typical USB port so you can watch the actual voltage. Your soldering is a little iffy, but everybody has to learn some time. The fact that you used the hot glue will keep everything from shorting. I say it is a good idea for those wanting to see such a voltage. Just practice on your soldering. Thumbs Up!

    2 replies

    thank you. I will fix my soldering skill. Thanks for look my work!

    thank you. I will fix my soldering skill. Thanks for look my work!