L.E.D. and Resistors

 

Standard
fixed type

Its
Symbol

 

In this section we will see how we can use resistors to
protect L.E.D's. This is achieved by the resistor limiting
the amount of current that can flow through the L.E.D. By
preventing too much current entering the L.E.D. we avoid
damaging it.

We can simply say that a resistor 'resists' the battery's
attempts to push too much current around the circuit and
L.E.D.

 

L.E.D. - Resistor Circuit Diagram

Notice that the + side of the battery connects via the
resistor to the Anode (+ side) of the L.E.D..

Resistors come in
many different types
and values- We need
to choose the right
one.

There are many different types of L.E.D. too as we have
seen and it is important to match them with the correct
value resistor.

  • If the resistor value is too big, too little current will flow
    in the circuit and the L.E.D. won't work.

  • If the resistor value is too small, too much current will
    flow, possibly damaging the L.E.D. permanently.

Resistors are measured in Ohms () - and this tells us its
resistance value.
A resistor can be smaller than1 ohm or
bigger than10,000,000 ohms.