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How to control output voltage of a 555 timer?

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ants

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Is it possible to control the output voltage of a 555 timer?

For example if I supplied 6V I might get 4V output. But what if I wanted an output of just 2V, how would I do that?

Thanks.
 

karesz

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Hi,
The 555 output is a so called "open collector" type, means; you have a resistor to connect for your actual output supply.
Select a working voltage for it properly to your output pulse amplitude needs...
Practically you can attenuate the output signal, or even select smaller/lower supply for the pull up , i.e. through a 2.1V Zener between supply & resistor.
K.
 

    ants

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IanP

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K., the output of the 555-timer is not OC ..
The output of the 555 comes from a high-current totem-pole stage ..
It can source and sink current (≈ +/-200mA) ..

The simplest way to reduce the voltage is a 2-resistor voltage divider .
Or you can use a potentiometer connected between the output pin and GND (see attached picture), or a resistor followed by a 2V Zener diode, and so on ..

IanP
:D
 

    ants

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ants

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I just did it, thanks both, I used a potentiometer.
 

karesz

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Hi,
Oh, Im sorry! I changed it with a U/F converter...
Im apologizing me.
K.
 

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