Multiple power supplies (many stages in project)

[fbchurch2009]

Hello,

I am working on a project and I had some questions about the power supplies... I have multiple stages:

I need: +9V for an arduino, +/- 12 V for a filter stage, and +5V for a digital part,

I think I have to connect all of the grounds together to make it work properly right? I guess I could just buy some voltage regulators that will take the +/- 12 and transform it into the 9V and 5V that my circuit will need later on? How do people normally go about this?

Thanks!

 

[Anon_LG]

Yes you are right about the grounds connecting and that you can use voltage regulators, you will need a 0 volt rail (the common ground), a +12 volt rail and a -12 volt rail, the voltage regulators will go between 0 volts and the 12 volt rails, find a 5 volt regulator with suitable power ratings and a regulator outputting a suitable voltage for the arduino. If you could provide a schematic this would help. If you do not have one yet google "Yenka". I hope this helps,

 

[Arouse1973]

If you can run your filter from +12 Volts only then this reduces your regulator count by 1. So you will only need a 12, 9, and 5 Volt regulator. If you did need -12 Volt then I wonder how you will process this on a 5 Volt system.
Adam

 

[BobK]

Hello,
I need: +9V for an arduino, +/- 12 V for a filter stage, and +5V for a digital part,

Are you sure you need +/- 12V for the filter? I am assuming opamp based active filters. There are many single supply rail to rail opamps that might work okay off you 9V or even 5V supply, depending on the range of the signals they are handling.

Bob

 

[fbchurch2009]

I don't have a schematic unfortunately. Well I guess I could use single rail op amp, and I guess I could just use 9V instead of 12V. So how would this work... I would have one wall adapter (9V) and I would run that into the arduino. Then I could just take 5V and 9V from the arduino for the other parts of the circuit? Im not sure if I can use 9V from the arduino can I?

 

[Arouse1973]

I don't have a schematic unfortunately. Well I guess I could use single rail op amp, and I guess I could just use 9V instead of 12V. So how would this work... I would have one wall adapter (9V) and I would run that into the arduino. Then I could just take 5V and 9V from the arduino for the other parts of the circuit? Im not sure if I can use 9V from the arduino can I?

In your first post you said you needed 9 Volts for the Arduino, so did you look to see if it will take 9 Volts? Then a regulator on board for the digital circuitry. Why don't you look at the data sheet for the Arduino your thinking of using, which you don't mention btw in your first post.
Thanks
Adam

 

[BobK]

The Arduino is going to have a 5V regulator, and, assuming you do not need too much power, you could power your other 5V circuitry from it. The same with the 9V, just make sure there is enough power for everything.

Bob