Beginners: please read this post and this post before posting to the forum.
0 Members and 1 Guest are viewing this topic.
I understand it is need to go from say 5v to 3.3v, but that's about it. Why do you need a chip for this? Couldn't you just use a voltage divider?
5v output to 3v input may use a single limiting resistor. the higher voltage is clamped by internal zeners.
Perhaps you could explain your application a little further please?
Bidirectional level shifters are easy, btw. You need one N-channel MOSFET, and a pull-up resistor on each side if that side isn't already pulled up. If each side is already pulled up, it's a single MOSFET transistor to shift levels bidirectionally. If you have many lines to shift (3 or more) then a simple chip, that also includes the pull-ups, may be worth it, because it will use less board area than discrete TO-92 MOSFETs like BS-170 or 2N7000 or whatever.
those Zeners aren't generally specified for continuous operation.
I have a sensor that outputs an analog voltage at 3.3v
Make sure it's low impedance enough to be able to drive the ADC inputs!...An alternative would be to re-buffer with an opamp set for partial gain.
the only real confusion if any was use of "bbb". normally this refers to avr Bare Bones Board.
imo simple divider is best. ratio but not actual values would be the concern. a cap not only solves the impedance issue there but added benefit of reducing noise.
An alternative would be to re-buffer with an opamp set for partial gain.