Breadboard Power Supply Tutorial

Battery is not a cost effective. Not always we use micro controller. Here is a guide on Breadboard Power Supply Tutorial for all situations. Most of us need a multipurpose solution which works in most of the situation, is cost effective, stable, reliable and most importantly – does not give a huge pain to make it usable.

Breadboard Power Supply Tutorial : AC/DC, Voltage, Amperage and Multimeter

You will get a below $5 Multimeter on Amazon or Ebay. First buy such one even if you have a very good multimeter. Most of the stuffs we use are Chinese with no Quality Control. Even a good Multimeter can die while testing. We listed the important meters used in DIY electronic works. Without the multimeter, you can not test the consistent voltage supply at a particular amperage. The strength of an electric current is expressed in amperes. It is quite important to know, regardless of the voltage, AC/DC :

1. 250 milliampere can run for example an Arduino board, this will not kill you if the voltage is under 3.5 volts.
2. 500 milliampere to 1 Ampere is used run an Arduino board with load, this is not quite safe amount if the voltage goes above 5V. You can get in to hospital with a simple car battery’s shock.
3. 2 Ampere is a dangerous warning with even 12 v rating. In very short, your family members celebrate with your photograph if you remain in contact for probably more than 1-2 seconds.

DC shock is more dangerous at the same voltage than AC shock. If you know nothing, kindly use a battery. In US, the mains is set to 110v. In India it is set to 230v. Manufactures usually make things (which are intended to be used on mains) which can handle 100v to 240v. Apart from Amperage, Voltage, another point is Frequency. India’s home usage supply is at average, consistently 50Hz. China possibly uses 230v, 60Hz supply.

Breadboard Power Supply Tutorial : Understanding the AC/DC Adapters

Possibly you have hundreds of various type of AC/DC Adapters at home. They have various names including chargers. Their basic difference is at connector, apart from the voltage supply part. Some can have mini USB connector at the end.

These are exactly what are desired as external power supply instead of battery. That is why human uses adapter for portable cassette players to DVD players. A good brand’s external power supply via these AC/DC adapters actually not bad. But we need more precise control.

We are covering this thing in three sub-headers.

Breadboard Power Supply Which Will Work For Boards Like Arduino

Arduino has clear official guide on their website. Apart from USB, you can use a 7.5 – 9V, 500 mA AC/DC Adapter with a round jack. You can read them on their on official website.

But the fact is what, for the breadboards, we usually need 3V to 5V voltage with 500 mA rating. How many AC/DC Adapters we will buy with various output ratings? That is why, there are AC/DC Adapters which has various plug ends with a kind of mechanical regulator to switch within various voltage outputs, these are called universal power adapters.

They were never hugely costly before. Now their cost has been increased due to popularity of DIY electronics. You frankly need to invest time to find one such AC/DC Adapter at a cost not more than $3. There is practically no meaning of buying a very costly AC/DC adapter as we will or the boards will “regulate” the input. Only you need to check with multimeter whether the output remains consistently right. Their performance might decline with load.

Voltage Regulation

It is a good idea to use a small chip like thing called integrated circuit voltage regulator on baseboard regardless of type on input. As they are basically derived from the mains and cost very low, they can blow the unit. Such devices are popular because they require few or no external components and provide the functions of pass element, voltage reference, and protection from overcurrent in one package.

These are also known as linear regulator and usually comes as a three-legger – an input pin, ground and an output pin. Typical example is a LM7805. They have good regulation and are easy to use. Main drawback is that they are not efficient. The load current passes through the regulator and causes a voltage drop there, like the series resistor would. If 5V circuit draws 1A you will draw that 1A from the 9V, so the load’s 5W will require 9W from your power supply, that is an efficiency of 55%.

For our work this is enough. A switcher or SMPS is the solution used for computers. Basically 230v like higher supply is actually not required at home, they are high for other reasons. More the power gradient will go towards the low, more heat will be generated. In other words, you can build a thing as DIY which will eventually regulate the DC voltage – be it via battery or AC/DC Adapter. More times you’ll run through various regulators, more heat will generate at the cost of decline in electrical parameters.

When we are converting mains AC supply to 9V, there is once conversion. Again when we are making that 9V to 3V on baseboard, we are regulating it twice in ( probably ) two methods. This control and regulation of voltage is a specialty in engineering like Orthopedics in medical science. Just know that passing twice is safer for the components. If we used a 1.5V battery, we would not control and regulate so much. A 1.5V source can not kill a LED light so easily like 12V supply. We are omitting the frequency and amperage part to make it simply understandable.

MB102 Breadboard with YwRobot MB102 Breadboard External Power Supply

There is ready made solution by the country named China. MB102 Breadboard is a kind of “standard” breadboard. Along with it, a probably good Chinese company named YwRobot, manufactures a Breadboard External Power Supply which has a black color board, yellow plastic components, a green LED, an USB port without any manual, reference, documentation. What we found, this is the official website of the company :

If you can luckily buy the original component (costs $2) you will get an anti-static bag. What we have found about this YwRobot MB102 Breadboard External Power Supply so far :

1. The manufacturer is careful, otherwise they would not supply the anti-static bag
2. This YwRobot made MB102 Breadboard power supply is a plug-in power supply which simply plug-in to the breadboard.
3. It is intended to use an input of 9V 500mA supply. You can use a battery or an AC/DC converter to supply within 6.5 to 12 V DC current. We think 12V is too much for it, it will get hot faster.
4. It has switch to regulate to 3.3V and 5V output.
5. It used two AMS1117 voltage regulators.
6. There is  diode protection for amperage surge.
7. We think that 9V is the optimal input for it.

Breadboard Power Supply Tutorial : Joining the Story

So basically if you have a 9V 500mA AC/DC Adapter, it will work for Arduino directly plus you can use the YwRobot MB102 Breadboard External Power Supply with it. You will need fan to cool the unit for higher voltage supply for longer period.

We purchased a ready to use useful kit from Ebay (it was the last kit) at $6.50 which included – (1) 400 point breadboard (2) One 2.1mm DC jack/plug, not soldered (3) 9V battery connector to connect with the DC jack/plug (4) 25 pcs male-male jumper wires of 15cm length (4) YwRobot MB102 Breadboard External Power Supply.

The package probably called MB102 Kit. 9V battery connector and 2.1mm DC jack/plug were extra plus from that seller, else you’ll get the same things from other sellers all over the Internet at around $7.50. A midrange 9V 500mA AC/DC Adapter costs $10. This is the easy Breadboard Power Supply Tutorial at the end. That kit plus 9V 500mA AC/DC Adapter or if you have too many breadboards, then buy that YwRobot MB102 Breadboard External Power Supply at $2.00 separately. We actually have 4 YwRobot MB102 Breadboard External Power Supply units, the whole system can not carry too much pay load. Finally test with the cheap multimeter. We have not discovered the full function of that USB 2.0 female plug.