Debouncing....at About 1Mhz

Here's a single-prop-delay version, which could be done in about 3 ns with one of the tiny-logic parts.

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I probably wouldn't do this in production, because the switch thresholds of cmos schmitts aren't very tightly defined. My other circuit is more predictable.

There is likely a variant that uses slow negative feedback that would be demonstrably reliable but preserves the 1-gate delay. Haven't worked that one out, but it feels like there's something there.

John

Reply to
John Larkin
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John Larkin snipped-for-privacy@highNOTlandTHIStechnologyPART.com posted to sci.electronics.design:

You are welcome to any thoughts you want. Please remember that the "input" is coming from a reasonably fast comparator as it is.

Reply to
JosephKK

John Larkin snipped-for-privacy@highNOTlandTHIStechnologyPART.com posted to sci.electronics.design:

I think i see where you went, that is kind of slick. Has to be a non inverting ST.

Reply to
JosephKK

Fred Bloggs snipped-for-privacy@nospam.com posted to sci.electronics.design:

I think they made the original, i used some knock off a mere 20 years ago. It did the job and was cheap. If i was trying to make a real design today i would be looking for an AHCT equivalent.

Reply to
JosephKK

John Larkin snipped-for-privacy@highNOTlandTHIStechnologyPART.com posted to sci.electronics.design:

Maybe, maybe not. Have you carefully analyzed all the propagation delays? What happens with a fast AHCT equivalent (is the '221 close enough?)?

Reply to
JosephKK

John Larkin snipped-for-privacy@highNOTlandTHIStechnologyPART.com posted to sci.electronics.design:

Would not work in this case. As previously stated signal is from a comparator.

Reply to
JosephKK

What difference would that make? The input is a logic level, and its time behavior has been defined.

Yes, there is a simple fix that allows reliable operation with real-world cmos schmitts. It's sort of obvious.

John

Reply to
John Larkin

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Best regards, Spehro Pefhany

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speff@interlog.com             Info for manufacturers: http://www.trexon.com
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Reply to
Spehro Pefhany

Neato..a differentiator warping the signal into the hysteretic levels... Nope...I didn't guess that one.

One wild idea I had was to try and use a 4.5nS LT latching comparator in some fashion.. But nahhh.. (No I'm not affiliated with LT in anyway..)

D from BC

Reply to
D from BC

I'll give you simple, but the other descriptors are in your dreams. I will not get into the details of the inferiority of your 'design' other than to say even a chimp would know that mixing RC's into a first occurrence event detector makes no sense.

Just more of your delusional fantasies...must be the Lipitor has corrected your testosterone deficiency, how does it feel to be able to grow a mustache for the first time in your life...

Reply to
Fred Bloggs

[snip]
[snip]

Neato! A non-repeatable "solution" ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
         America: Land of the Free, Because of the Brave
Reply to
Jim Thompson

Clearly it needs some delay. Maybe I should have used Jim's magical "Delay" black box.

I don't suppose you noticed that the RC drives the D pin of the flop. Hell, you obviously don't understand the circuit at all.

So design and post something and quit whining.

I've had one since I was 19. I was doing presentations to aerospace companies, like Lockheed and Boeing, and I just looked too young. The moustache helped a little. We got the contracts, so I suppose it did.

John

Reply to
John Larkin

Hey, Jim is actually Fred in disguise!

John

Reply to
John Larkin

Waveforms that only droop the part of the waveform you WANT to droop (trying to make your case) don't quite do that in the real world.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
         America: Land of the Free, Because of the Brave
Reply to
Jim Thompson

Circuits process waveforms the way I want them to, because I design them that way.

Are you suggesting that I don't understand how RC circuits respond to waveforms? The only alternative seems to be that you don't. So you must be Fred, qed.

John

Reply to
John Larkin

[snip]

Funny, your circuit doesn't produce waveforms exactly as you sketched them.

Put some numbers on a real circuit, post it, and then let the mob evaluate its efficacy.

Or are you chicken ?:-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
         America: Land of the Free, Because of the Brave
Reply to
Jim Thompson

Of course not. That's why they call it a "sketch." And since the component values aren't specified, it couldn't do anything "exactly."

So you *don't* understand it! That's interesting.

John

Reply to
John Larkin

[snip]

Your recent responses have become of such a subterfuge level I have to conclude you're a leftist weenie. Bye!

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
         America: Land of the Free, Because of the Brave
Reply to
Jim Thompson

Well, either you see it, or you don't. I guess you don't.

John

Reply to
John Larkin

Oh, I see it. It's just part of your leftist weenie persona to duck by claiming I don't understand.

Your circuit's Thompson Reliability/Repeatability Rating == 0

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
         America: Land of the Free, Because of the Brave
Reply to
Jim Thompson

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