encoder

I am trying for the Adruino Uno to read a pulse from a optical encoder. I have the index from the encoder going to pin#2 as an input. What kind of voltage change can the Adruino see? Right now at "index" I get the 5 volts but out of index the voltage stays at about 2 volts. Is this voltage change enough for the Arduino to detect it from "LOW" to "HIGH"?

jcann9960: I am trying for the Adruino Uno to read a pulse from a optical encoder. I have the index from the encoder going to pin#2 as an input. What kind of voltage change can the Adruino see? Right now at "index" I get the 5 volts but out of index the voltage stays at about 2 volts. Is this voltage change enough for the Arduino to detect it from "LOW" to "HIGH"?

The forward voltage of a (silicon) diode is about 0.7V, you could try that to drop your LOW. there are more electronic methods... transistor, level shifter, resistors, etc...

Assuming Uno you need about 5V to register a HIGH, but you can look at the datasheet for that.

BulldogLowell: The forward voltage of a (silicon) diode is about 0.7V, you could try that to drop your LOW. there are more electronic methods... transistor, level shifter, resistors, etc...

Assuming Uno you need about 5V to register a HIGH, but you can look at the datasheet for that.

The datasheet says below 1.5 is LOW and above 3.0 is HIGH, but a recent thread in Project Guidance has shown that may not be the whole story.

Delta_G: The datasheet says below 1.5 is LOW and above 3.0 is HIGH, but a recent thread in Project Guidance has shown that may not be the whole story.

my error! I meant 3.0V...

thanks!

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