How to Make a USB Breadboard Power Supply
by miniProjects in Circuits > Electronics
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How to Make a USB Breadboard Power Supply
I purchased many USB breadboard power supply from market but none of them fit on my bread board. Reason being non standard dimensions of breadboard. Holes are 2.54 mm apart, but total size is variable.
Hence I decided to make one by myself which could fit all my breadboard.
It was really simple when I realized that my computer gives me regulated 5V.
What All Things You Will Need?
You will need following things to make this small supply-
- One USB type A male connector
- small piece of general purpose circuit board
- few 2 pin male and female connectors
If you are confused go for images.
Bit of Theory
We need to make a bit of mechanical and electrical considerations.
Mechanical-
There are 4 pins in a USB type-A male connector, spacing between them is not uniform, look at the attached image. spacing between pin number 1-2 is 2.54 mm, 2-3 is 2.04 mm, 3-4 is 2.54 mm. Now standard pitch in General purpose Circuit Board(GCB) and breadboards is 2.54 mm.
Connector wont fit exactly or directly in your GCB , we will have to stretch them a bit.
Electrical-
pin-outs- As you can see in attached image outer most pins are 5V and GND, and inner pins are D+ and D-. we will be using 5V and GND pins.
Ok, you get 5V but how much current. For USB 1.x and 2.0 current is limited to 500 mA, for USB 3.0 its 900mA. So if your circuit under test demands current that is less then this ratings, you will never run out of batteries. Supply voltage can vary from 4.75 V - 5.25 V in case of USB 1.x and 2.0, 4.45 V - 5.25 V in case of USB 3.0.
Assembly Time
Just connect 5V pin and GND pin to respective jumpers using solder. I have attached images for your reference. Just look at them if you are confused.
Testing
Just hookup your multi-meter to breadboard where you can probe the output of our homemade supply. If you get voltage in the range of specification of USB you are ready to go. Else check for Short and Open as these are the only two faults that can happen. If its Short touch the solder it feels hot.(I accidentally did it while making this!!!!).
OK, so finally you have a handy tool which will give you 5V with out any problem (Of course you need a PC or a Lappy).
Thanks for reading, I am also attaching a link to my video for the same feel free to have a look.