regulation of regulated voltage?

[bluesmoke]

Hi,

I am designing a PCB that have some analog components including camera and accelerometer etc. The board is to be interfaced with another (micro-controller) board. A 3.3 V regulated supply and an unregulated supply is available at connector pins. I want to have local regulation on my camera board. Here I need your input that which solution would be best:

a) using the unregulated supply for input to my local (camera board) regulator.
b) using the regulated supply for input to my local regulator.

Thanks

 

[RobG]

The only reason I can think of to run the camera regulator off the regulated supply would be if your camera circuit needs more isolation from the unregulated supply. I doubt this is the case so I'd run off of the unregulated supply. This will increase the isolation of the two circuits and also reduce the amount of power that the first regulator has to provide.

 

[Pjdd]

What supply voltage does your camera need? And what's the nominal voltage of the unregulated supply?