Limiting the voltage

[adrianvon]

Hi,

I have an analog voltage which varies from 0V to 5V. Is there a way to only allow voltage above 3.5V to pass using a single small component?

Thanks in advance.

 

[Nigel Goodwin]

You need to be FAR more explicit about EXACTLY what you're trying to do - there's no where near enough information in your first post.

 

[cowboybob]

Oops. Misread post.

 

[kubeek]

Single component - no, not really. A few components, maybe. How precise and stable does the threshold need to be? What current is to be passed, and how much of it can you use to feed the controling circuit?

 

[alec_t]

A 3.5V zener diode? Strictly speaking it's current which 'passes', not voltage.

 

[NorthGuy]

I wonder what should happen if voltage is below 3.5V? If you cut it off, it'll be 0V, which is below 3.5V.

 

[cowboybob]

Hi,

I have an analog voltage which varies from 0V to 5V. Is there a way to only allow voltage above 3.5V to pass using a single small component?

Thanks in advance.

Not exactly a single component circuit (I doubt there is such a beast), but a comparator arrangement like this might suit your needs:

There are additional modifications that can be used to handle various current requirements.

Here's the site with more examples... **broken link removed**