5V DC Power Supply for Breadboard Using Phone Charger




Introduction: 5V DC Power Supply for Breadboard Using Phone Charger

Hello Everyone,

In this instructable, I will be showing how to make a very simple 5V DC power supply for breadboard to power your circuits using an old (or a new) USB phone charger. Phone charges usually have an output DC voltage of around 5V . So let's get started.

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Step 1: Materials Required

Most of the parts used can be found laying around in our homes. Below is a list of materials I needed.


1) An Old ( or a new) USB phone charger with cable.

2) BreadBoard

3) Single strand wire

4) Multi meter (to test the output)

5) Wire cutter

6) Solder (optional, makes things more convenient)

Step 2: Altering the USB Cable

This is the major part of this simple project, once done , the project's almost completed.

Cut the USB cord into two using a wire cutter . Here we will be using the part that fits into the USB charger. At the cut end remove a part of the insulation using a wire cutter or a blade (Be careful while using a blade). The USB wire has four smaller wires inside the outer layer. Out of which , two wires are used to transfer data (here they are the white and green wires) and other two carry current/power (here, they are the silver and red wires . Refer to the 4th picture in this step to see what I mean.) these are the wires we need. This may vary from wire to wire, so determine the power wires using a multi-meter. Cut the data wires . We will end up with the two power strands.

Step 3: Soldering the Wires and Connecting to the Phone Charger.

Solder the power wires of USB cord to two separate single strand wires. This is mainly done to make it more convenient while connecting to the breadboard. Remember the insulation we removed earlier, it can be used as a jacket to cover the soldered part.

Finally connect the USB cord to the phone charger.

Step 4: Connecting to the Breadboard, Powering on and Testing the Supply.

Connect the two single strand wires to the bread board and switch on the power supply and now we have a 5V dc power supply to power our circuits .

In my case the output voltage was fond to be 5.20 +/- 0.05 V.

PS: The same method can be followed to power any other device that need 5 volts(or less, using suitable voltage dividers) to run.

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    6 Discussions


    3 months ago

    Very handy, but be careful. If the charger has a second charging cable, *don't* use it. If something goes wrong on the breadboard, it can backflow power to the other cable and damage your device. I blew up a Raspberry Pi in that way.


    2 years ago

    Is 5.2V safe for the sensors?


    Reply 2 years ago

    as _electronicsguy says below, NEVER use 5V or higher for ones marked Maximum 3.3V (they have an actual limit of 3.6V but that's still pushing the envelope.) .2V won't harm 5V rated, but anything above 5.4-5.8 might.. the difference, is TTL (5V) and CMOS (which used to be 6-12V before, now refers to 3.3V).. Alternate, if a USB phone (or other device) charger is too low a amperage (most rate from 100mA to 500mA) there's always the overkill solution, using one of the many converted ATX supply projects listed, and IF you can still find one, unsolder the molex power connector from a 3.5" Floppy drive (do they still make those?) unbend the pins, and use them as a power connector if the supply still has the mini-4 pin power connector..


    Reply 2 years ago

    It depends on the sensor . Some work fine at 5v supply and some may need less than 5v (like around 3.3v) . So look up how much volts the sensor can handle and bring down the 5v supply to required volts using suitable voltage divider circuit. Otherwise, some sensitive sensors may end up being damaged. So check before connecting the sensor.

    DIY Hacks and How Tos

    I do this all the time with a USB output from my computer. I am always prototyping with my laptop nearby, so it makes a really convenient power supply.


    Reply 2 years ago

    Yes , even I have been using it from a long time and found it really helpful. So wanted to share this with everyone through this instructable.