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Old Nov25-09, 11:30 PM                  #1
line2

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Question about a circuit using a 555 timer

Here's the drawn circuit: http://imgur.com/DGo9M.png

R1 is 10k Ohm resistor
Pot is a 100k Ohm potentiometer
C is 1.0uF Electrolytic Capacitor

My question is, what happens when the potentiometer is turned down to 0 resistance? Would the circuit fry?

thanks
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Old Nov26-09, 12:24 AM                  #2
vk6kro

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Re: Question about a circuit using a 555 timer

Pin 7 discharges the capacitor after it has fully charged. So, if you made the resistor almost zero, the capacitor would discharge very quickly.

This produces an output that is mostly high but with a very short low time.

If you could make the resistance zero, the output would stay high all the time but there is a risk that the transistor that discharges the capacitor (inside the chip) could get damaged, especially if a large electrolytic capacitor was used.
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