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false signals triggering 555 timer

A

aha

anybody knows something about this?
i got a good 7812 power supply with big capacitors and some small mkm ,
and pin 2 connected to + with a 10k resistor wich improved a lot,but not all
of the error triggers.

thanks.abe

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M

Mark J.

In news:[email protected] (aha):
anybody knows something about this?
i got a good 7812 power supply with big capacitors and some small mkm ,
and pin 2 connected to + with a 10k resistor wich improved a lot,but
not all of the error triggers.

thanks.abe


Place a 100nF (0.1uF) low-ESR cap right next to the 555's power pins. This
should fix it. If not, is it the CMOS 555?
 
L

loedown

Hi All,
I seem to remember something about a 100nF between earth and pin
5, but it has been a long time since I played with a 555

Paul
 
B

Bob Parker

Yeah, you should do that and bypass the supply pins with a
disc/monolithic 100nF as the previous person said. 555s are notorious
for false triggering. I've had embarrassing first-hand experience in
an old Yellow Light car alarm which was based on them...

Bob
 
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