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[on:]

hey, i have a simple question regarding power and power source.

so the arduino lets me send 5v to my sensors.
i am using the PIXART infrared sensor from the inside of a wiimote.
it needs 3.3v. i have built a regulator that powers the sensor from USB power (5v of course) regulated to 3.2v.

now, my question is, can i use the same regulator circuit to convert a branch of the voltage from arduino down to 3.2v for use with the PIXART while using the unregulated 5v from arduino on other sensors?

i image the answer is yes, but the reason i ask is because of ground - since ground is the comparison, does it matter if the upper threshold (3.2v, 5v) is different for different parts of the circuit??

thank you for your time.
nym

[Reply #1 on:]

You need the grounds all tied together.

The arduino boards can output 3.3V (at differing mA capabilities), how much current are you using?

[Reply #2 on:]

so the arduino lets me send 5v to my sensors.

Voltage isn't sent.  It is a potential that is provided.  Current isn't sent either, it flows.

does it matter if the upper threshold (3.2v, 5v) is different for different parts of the circuit

If it mattered, almost no electronics would work....  

Ground isn't really a "comparison", it is the "reference."  All components need to have a "common" "reference" (quotes added because those are other words for "ground").  Ultimately you are trying to make current flow between a higher potential and a lower potential.  To make life easier, we commonly call that lower potential "Ground." 

So if your regulators and all components they are connected to share the same ground (reference), current will flow.

[Reply #3 on:]

excellent, thank you.