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"5 volt limit" circuit? Answered

Is there a circuit that will take a range of voltages and make all of the voltages that are over 5 volts be 5 volts 
like so:
3.5 => 3.5 
4.2 => 4.2
4.9 => 4.9
5.1 => 5.0
6.3 => 5.0

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steveastroukBest Answer (author)2010-06-07

Yes, its called a level clipper. The easiest way is show in the circuit for my "car-bar duino" board,  in the top right of the schematic

This clamps the input to the supply rail or ground +1 diode drop.

Steve

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flybye22 (author)steveastrouk2010-06-07

does that mean that i wont be able to clamp it at exactly 5V? Also, what diodes did you use, i gave the instructable and schematic a quick look through and did not see parts anywhere.

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steveastrouk (author)flybye222010-06-07

Not critical for any component really. It depends a little on just HOW much higher than 5V you go, if you're expecting no more than another 5V, say 1-5K. Steve

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SoloUnNick (author)2012-08-06

Hi, I'm interested to Jayefuu's circuit, but with 4,6-4,7 volt limit.

Is it possible to reduce output voltage, changing resistances?

Zener diode from GND to 12V....or from 12V to GND? I'm sorry but I am very ignorant

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Jayefuu (author)2010-06-07

This circuit clamps the output between 0 and 5V. Used it on my final year project. Change the resistors if you have a different supply voltage.

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steveastrouk (author)Jayefuu2010-06-07

That's funny I have a circuit just like that one.....

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ARJOON (author)steveastrouk2010-09-16

me also. I think Google is the responsible for

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Jayefuu (author)steveastrouk2010-06-07

I thought since I'd already drawn the diagram I might as well pass it on :D

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steveastrouk (author)2010-06-07

Better to replace R2 with a Zener diode. Steve

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steveastrouk (author)2010-06-07

You can also just put a limiting resistor and a 5V zener diode at the input. Steve

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