I'm still pretty new to electronics, and this is my first time on the EE StackExchange, so please bare with me 🙂
I'm currently working on designing a schematic for a quick prototyping board, in Eagle, for use with the Intel Edison. On the board there are a couple chips that require 5v to operate (an FE1.1s and a PCM2902E), and the Edison needs 3.3v to run.
In my schematic, I have a standard barrel jack and two screw terminal that I'm going to use to power the board. Now as I have a history of acidentally blowing stuff like LEDs, some chips, and speakers by acidenatlly applying to much voltage, or acidenatlly using a wall adapter set too high, I want to install some protection. (Especially since the Edsion don't have any type of voltage regulator, I don't want to fry a $50 board!)
The idea is that the user can input any voltage (5v and above, say up to 12v) through the screw terminals or the barrel jack, and the board will shift to voltage to the levels it needs.
Right now, using this tutorial I have a 5v voltage regulator in my schematic to shift the input down to the 5v I need to run the chips. Now I need another circut to shift it down to 3.3v so I can power the Edison
simulate this circuit – Schematic created using CircuitLab
Whats the best way to go about shifting the voltage down to 3.3v for the Edison? and is there a better way to shift the unknown input voltage (max of 12v) to 5v?
Best Answer
LM78XX is a good option to solve your problem, but I strongly suggest you to investigate on LM2596 and mic29302. These regulators are much better than the old (but always effective) LM78XX series. If you are new to electronics, I recommend you to start with the newest available components. You will need some additional capacitors for these regulators but it's nothing hard, you will find all required information in the datasheets. Also, using LM2596 you can adjust the output voltage by changing the resistors values, so you can re-use these components in future projects. LM78XX series has defined output voltages that cant be changed.