The above circuit worked to let a 5 Volt servo work on a 3.3 Volt signal. This DOES NOT convert power so connect the servo power connections to 5 Volts and ground. This only converts the low power signals (before this my servo wouldn't move!)
Now, the resistor is 1000 ohms or 1 K (brown, black, red). Wattage isn't citical. The diodes are 1N914 or 1N4148 any good silicon (Switching) diode should work.
If you have a really fast signal I am pretty sure this wouldn't work. It sure worked well for my 5 Volt servo!!! (Re-check all connections before you use this and as usual, your milage might vary...)
Maybe it functions as a reverse voltage protector or a overvoltage protector???
I don’t know, I haven’t did any circut analysis. The image is copied direct from a pdf document.
I just know the circuit works and now the “fear” of using a 3.3 volt processor with hardware needing 5 volt signals (like anything related to the Arduino, a 5 volt system).is gone.
More and more of the new systems will be 3.3 volt, as that is becoming the new “standard”. Being able to connect to them is importanf.
NOTE: I chose the 1k (1000 ohms) resistor, other values might work better (depending on the equipment used).
(5 volts to 3.3 volts is even easier using a few resistors as a voltage divider, and just a few calculations.)).
I think this (very cool tip) should be (cleaned up in respect of the comments) and then be posted as a “Tip / Walkthrough” -> That way people can find it easier, thanks