Series Circuit Defined

A series circuit is one in which items are arranged in a chain, one following the other, so the current has only one path to take. The current is the same through each item.

Series circuits are used for several reasons:

1. To increase a voltage source.

The following is true of any standard battery, but let’s use the AA battery as an example. If you put one AA battery in a circuit, you will have a power source of 1.5 volts because that’s the voltage of a standard AA battery.

AA-battery

 

If you want 3 volts, you can place two AA batteries in series which gives you 1.5 V + 1.5V, which equals 3V.

AA double batteries and lamp

 

 

 

 

Put three AA batteries in series and you will get 4.5 volts, etc.

More coming soon.

 

Also see: http://physics.bu.edu/py106/notes/Circuits.html

Your First Electronic Circuit!

So you want to learn about electronics! Good for you! The sky is the limit when it comes to this field, but let’s start with a very simple circuit.

Lighting up a light emitting diode (LED).

The entire circuit is very simple — it consists of an LED, a power source (batteries), and a resistor to limit the current through the LED.

Light emitting diodes will emit light when a voltage is applied to them and current flows through them. Different colors and types of LEDs may require different voltages and currents, but a standard red LED requires 1.7 volts and .02 amps (20 milliamps, or 20 mA).

Here is a how to build your circuit if you’re a very beginner without many tools yet.

basic LED circuit

I have two AA batteries (1.5 volts each) that are connected in series to make about 3 volts. (Click here to learn about series connections.)

They are in a little battery holder with alligator clips that I soldered on to make the connections easier.connected to the LED and a current-limiting resistor.

I used an extra alligator clip to connect the resistor to the LED. You could use a paper clip, or just wind them together.

Here is what the circuit looks like in a schematic diagram:

basic_circuit_schematic

Even this simple circuit needs a little forethought.