What do I do now

BringMeEs&KsM897

New Member

• Sep 15, 2011

• #1

I made a timer circuit with the TLC 555 timer I made it as shown below.









But when I connect the - to the common the LED is off and nothing happens,
but when I disconnect the LED turns on. I do not understand can any one help

 

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ronv

Well-Known Member

Most Helpful Member

• Sep 15, 2011

• #2

You need a resistor of about 220 ohms in series with the LED.

 

ericgibbs

Well-Known Member

Most Helpful Member

• Sep 16, 2011

• #3

But when I connect the - to the common the LED is off and nothing happens,
but when I disconnect the LED turns on. I do not understand can any one help

Click to expand...

Hi,
Change the 1K to 100K, the LED off time is far too short, you will never see it go out.!

Also place a 330R is series with the LED.

Look at this circuit

 

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Last edited: Sep 16, 2011

BringMeEs&KsM897

New Member

• Sep 16, 2011

• #4

thanks guys! that totaly worked