The Small Solution to the BreadBoard Power Problem

We all use breadboards for prototyping. We all use DC Adapters to add power to them. But i used to do this by simply taping the wires to the DC Jack and then use it on the breadboard. This was always loose and clumsy and i always has to find out the polarity as some manufacturers are smart to not ground the outer shell. I even blew an IC this way once, when it was taken for granted. Some manufacturers do keep the outer part (shell) as positive while ‘most’ keep it negative!

Duh!

So, I found out a better way to make breadboards compatible with DC jacks and polarity issues. This is small board with headers that plug into the breadboard. It has a diode to make sure nothing flows reverse and a small 0.1uF cap to provide some rudimentary decoupling.

I quickly designed the board,etched it and filed it to shape.

Board design

Board design

Schematic

Schematic

Before the bath

Before the bath

On the breadboard

On the breadboard

And Tada! I have one little board that has ‘inherited’ two worries ! Two things of the “To-Worry-about” list 😀
This shall end the biggest #issues while using #breadboards #DCJacks and #PolarityCheers!

Micro Adjustable Bread-Board Power Supply

I always wanted an adjustable Power Supply that would shell out about 1-1.5A for most of my applications as a hobbyist. But the Space they occupy and the price they come with are always a problem. So, I thought of building a very small power supply that would serve my purpose.

Having worked with LM317 earlier , i choose to build my around it. LM317 can give out about 1.5A according to the datasheets which is more than enough for most of my applications. Now the next hurdle was to make it as small as possible. The schematic is given below:

Schematic

Schematic

It took a couple of design iterations to make it suitable for a single sided board and i was finally able to come up with a very small one.
The size i was able to build was 3cm X 2.5cm with all components included on board.
Before making(etching,soldering) it was necessary for me to do some 3D- Rendering of the PCB so that i can have a better Idea of how the final board will look. I used Google SketchUp for the same. The Isometric image is provided below:

3D Rendered Board

3D Rendered Board

 

The Final Rendered Image

The Final Rendered Image

It took me a while to make the board as the Bourns Pot i had was faulty and the local store took some time to get it for me.The board has a heat-sink for LM317 glued using processor heat glue to dissipate heat.There is also a small switch that i managed to squeeze on the board and a diode..just in case you had polarity issues.

The completed board that i built looked like this:

Small and wastes no holes

Tiny and wastes no holes

This is the demo picture showing the output as 2.9V at a 8V input from a standard AC adapter.

In Action :)

In Action 🙂

Cheers and Regards,

IndianTinker 😀