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Max possible voltage on input of pins

Started by lagoru, September 14, 2015, 07:00:19 am

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lagoru

Hi all, recently I am interested in adding some external measuring devices to my cubieboard - long story short: I am building quadrocopter. And thus that I have one basic but important question: what is the maximum tolerance of voltage for input for cubie pins ? I know how to bind them, and use via file mechanism, but I am afraid that output (5V) of my measuring device (HCSR04 ultrasonic length measurer) might be just to much to handle by the pins. I have tried to find some informations about this all over cubie forums/wikis but I had failed in finding anything.


*sorry for bad english

@lex

The maximum voltage for input is 3.3v!
I am not a hardware guy, but 5v will damage the pin or the board.
Take a look at this: https://www.sparkfun.com/products/12009
I hope you find a way to keep going with your project.

lagoru

Quote from: @lex on September 14, 2015, 08:30:58 am
The maximum voltage for input is 3.3v!
I am not a hardware guy, but 5v will damage the pin or the board.
Take a look at this: https://www.sparkfun.com/products/12009
I hope you find a way to keep going with your project.

Thanks for response ;) So this is as I thought... good that I had doubts beforehand.
As for logic converters - I have heard that it is only good if devices have low level of Hz on communication (low Hz I2C, low Hz PWD etc.) - but not for analog devices (as one I am trying to connect) usually they have some kind of delay on conversion so reading might be wronged.

If anyone have other information (I might be wrong) please share.

As for solution - I think that I will use old fashioned circuits rule to drop voltage (two resistors, one between ground and signal second between signal and signal).