The 7805 is a 5V voltage regulator. It takes DC voltage from 8 to 30 volts and converts it to smooth and stable 5 volts. This is very useful for powering some sensors and other 5V parts. 5V is also the voltage that Arduino and most other microcontrollers use as their logic level.

It is good practice to always use the 7805 regulator when you are building any of the analog circuit examples mentioned on this site. That way you make sure that you don’t fry some of the 5V parts and sensors we have in the lab (use the 3.3V regulator when you want to work with the accelerometers and other 3.3V parts).

Breadboard example. Click the image for a bigger version.

You can also add extra capacitors on the input and output in order to make the voltage extra smooth.

  • 10 uF for the input
  • 1 uF for the output

Note! The parts we currently have in the lab are marked L7805CV.

Download datasheet.