As I'm new to Arduino,I was wondering if there is any good reason why, when connecting the output from arduino @ 5v logic level, to 3.3v level devices I could not just use a resistor potential divider (say 3.3k in series with a 6.8k, Nearest preferred values ( 6.8k to neg.)) from the output pin to neg. and take the feed out across the 6.8k resistor? This would save using level shifting IC's, etc.
Ive seen some designs where there is just a resistor in series with the output pin, but when it is coupled to a mosfet input device, the voltage at each end of the resistor is still 5v as no current is being drawn through it, possibly risking breaking down the input mosfet.
Your experienced comments would be welcome