Wednesday, April 27, 2011

The Root of all Juice

We're going to play a game. It's called, find the power source. Ready go:

Okay, maybe that one was little much, try this:
The answer we're looking for here is the 3V Battery. 

So what does this have to do with anything? Anyone who has ever have used an electronic device has encountered it. It's where it all begins, simply put, the supply of power. Whether it's a AA battery or a cord that channels the juice from the wall outlet. This symbol is the most important.

The electronics schematic symbol for a cell

It's the source of that jumbled mess up top, but it's also in every electronic device you'd come across. Ipods to plasma screens all run on that simple electron (electricity) producing source. The point of all this is that someone sat down with a pen and paper and started with that symbol and worked their way forward, manipulating the electric juice as it flows through the wires. 

Using a slew of odd looking components like resistors and integrated circuits, the electrical engineer is the master creator of all things modern.

An integrated circuit-not a 21st century centipede
Classic resistor
Objects like these are in charge of doing one thing, altering the electrical signal that passes through them. In the end, electronics are nothing more than tons of well-manipulated signals that are either ON or OFF. Imagine how a computer comes of that?

Sadly, the knowledge of electronics seems to be slipping away. It is fair to say we are riding on the backs of a small percentage of the population's intrepid electrical engineers who can take electrons flowing from a battery and turn it into music with a picture of the album.

Going Further:

While the symbol for a cell is the simple drawing of vertical and horizontal lines, there are other sources of power than just a battery (which actually is a combination of several cells).

Others include DC power supplies:

A representation of DC power-- what comes out of a AA battery

Or AC power supplies:

The power that comes out of the outlets

 Both are two different creatures and their behaviors are much different as far handling them in the circuitry. The symbols are not universal, but the idea is consistent throughout schematic drawings. For example look at the first image and notice that its power supply says: " +9 to 12VDC." It just means the juice ranges from 9 volts to 12 volts direct current (DC).


  1. 3V battery -- I guessed it right! Yesssss! ;-)

    Very interesting, Eric. I certainly hope electric engineers are handsomely rewarded for their work, especially since we take them for granted.

  2. Thanks for the lesson! There's just too much knowledge out there to keep track of all these little factoids.

  3. Love, love the use of graphics in this post. The first one compelled me to keep reading! Will share with my electrical engineer husband.

  4. Nice post, Eric, and great information. I definitely think our knowledge of electronics and circuits is waning - at least I can definitely say that I have very limited knowledge of the topic. Pretty sad considering how much electronics influence our everyday lives.

  5. Again bringing the nerd out in all of us, Eric. A lost art. My dad has no college education, but he knows all about this stuff. You know, electricians can pull down six figures...

  6. Yeah, especially for the reason I mentioned. With so few adept in the world of electrical engineering, combined with the growing complexity of the circuitry, I'd say they deserve it.