First off – i'm an EE noob, but i've muddled my way through a number of arduino projects, so have some experience there.
I'm building a breakout board for a CMOS camera sensor for use with an arduino mega (ATmega2560 mcu). The mega has a +3.3v and a +5v rail. The camera has two different VINs, one for the analog circuitry one for the digital. both are listed for a max of +3v, and one is recommended at 1.8, the other at 2.8.
My question is how do i get those voltages from the 3.3 rail – just make a voltage divider? Also, won't this also affect the logic levels dealing with the circuit? if i build a divider, do all lines have to run through one? do i need a level shifter?
a little lost here..
Best Answer
A voltage divider is not a good idea because the output voltage will depend too much on current draw, or it will always draw lots of current from the supply. A better idea is to linearly regulate the 3.3 V supply down to the other voltages you need. That will be somewhat wasteful of power, but if the arduino supply can handle it, it will be the easiest solution.
Whenever you say you need to power something at a particular voltage, you should also mention the current requirement. Since you didn't, there is little more specific advice to give. If it's only a few 10s of mA, then linear regulators are a no brainer. If it's 1 A then it gets more complicated, and quite possibly the existing power supply doesn't have enough extra to provide that power.