From: "Frank Bemelman"
References: <0001HW.B9CEF278023A90B81662EAD0@news.covad.net> <3DA9D6CC.email@example.com> <3DA9D9E1.firstname.lastname@example.org> <3DA9EE2A.B7CFD919@juno.com> <3DAAF96D.email@example.com> <3DAB71EC.DB68183C@juno.com> <3DAC2309.firstname.lastname@example.org> <email@example.com> <3DAFFA70.firstname.lastname@example.org> <email@example.com> <3DB1869F.649A02A4@bellatlantic.net> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org>
Subject: Re: How to get CMOS counter to drive a relay?
Date: Tue, 22 Oct 2002 19:07:43 +0200
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Organization: EuroNet Internet
NNTP-Posting-Date: 22 Oct 2002 17:09:43 GMT
"Frank Bemelman" schreef in bericht
> "Tony Williams" schreef in bericht
> > In article <email@example.com>,
> > Frank Bemelman wrote:
> > > Okay. The flyback causes the output to rise 2 volts above
> > > the supply, for a few ms, decaying quickly. (without the
> > > diode). I had it run for half an hour, sweeping the
> > > frequency from 1Hz to 100Hz. Tckckrrrreeeeetttssss....
> > > I also have to report that the 4060 finally died at 25V.
> > > It didn't suffer very long ;)
> > Try it the other way Frank..... with the free end
> > of the relay coil to 0v. See if there is any
> > difference when an output pin is thrown below 0V.
> > (ie, below the substrate.)
> I'll try that, if I can find another 4060. The first
> arrangement seems to work brilliant, I don't think it
> would have popped if I hadn't turned up the supply
> to 25V after the first half hour running it at 18V.
Okay, found another 4060. Relay from output to ground,
no diode. Vcc = 18V. Outputfrequency is 25Hz, and the
relay is clicking like mad. The undershoot is 1V below
GND, or 0.7V with diode. Voltage drop from the output
is 5V, so the relay gets 13V.
So it does not make much difference, both circuits
work equally well.('equally well', that's good eh).
I left this running for about half an hour too, then
turned up the supply to 25V and beyond.
This is interesting. It continious to work fine, until
it's >28,6V and starts to go funny. The 4060 dividers
are getting confused and the frequency changes. At 29,5V
it stops all together, BUT the 4060 does not die. As
soon as I lower the voltage below 28,5V it picks up
again. The relay gets 20V of this.
My benchsupply does not give more than 31V. This is
not enough to kill the 4060 in this arrangement.
The 4060 is now running at 28,5V, relay draws 40mA,
no diode. Oh, and no decoupling cap, and long wires ;)
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