[sdiy] CV --> microcontroller, how to limit input voltage?

[The Old Crow]

  Just use a couple of diodes.  For example: K of D1 to +5V supply, A of
D1 to I/O pin.  K of D2 to I/O pin, A of D2 to GND.  These will clamp the
input to 0~+5V (well, -0.7 to +5.7)..

  I typically use 1N4001s, but if the current load is light switching 
diodes (1N4148) are fine.

Crow
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On Sat, 10 May 2003, Bret Truchan wrote:

> * If a microcontroller I/O pin is configured for input, an incoming voltage 
> signal doesn't peak over 14 volts  
> * If the microcontroller I/O pin is configured for output, it still works. 
> (The output will always be 5Vfrom the microcontroller.)