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Mains voltage zero crossing detector with optical isolated output

Why do you say "yuck"? I don't like to be bothered by all these idiots who violate the do-not-call list. My present system doesn't ring AT ALL if you're in the "killfile", yet reports CID to all phones in the house... that's the problem I solved that commercial units don't provide. I'm just going to turn it around... ring only if you're whitelisted, voicemail opportunity otherwise... except if you're any 800 variant... then black-hole ;-)

Good grief! Though I do treat unexpected door-bell rings with caution. You never know when some nutcase, like Larkin, will go ballistic and show up at my door ;-) ...Jim Thompson

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| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson
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I'm surprised you didn't use a single AC out wart and do the AC -> DC
thing internal to the generator.
Reply to
John Fields

So a new client or long-lost relative would automatically be directed into voice mail? Ok, it's your phone.

[...] 
--
Regards, Joerg

http://www.analogconsultants.com/
Reply to
Joerg
[snip]

Yes

Yes, it is. ...Jim Thompson

-- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

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| 1962 | I love to cook with wine. Sometimes I even put it in the food.

Reply to
Jim Thompson

The problem there is that it wouldn't be 90-240 volt universal. We figured that a minority of users would want to line-trigger a picosecond-resolution digital delay generator, so the extra wart isn't a big deal.

--

John Larkin, President
Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro   acquisition and simulation
Reply to
John Larkin

Yuck :-)

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SCNR, Joerg

http://www.analogconsultants.com/
Reply to
Joerg

The next thing you know, you'll be getting phone calls from people on usenet. ;-)

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You can't have a sense of humor, if you have no sense.
Reply to
Michael A. Terrell

Actually, I do. Regularly. Seeking circuit help without the pain and agony of Larkin obfuscating a logical progression to a proper solution. ...Jim Thompson

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| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

That analogy doesn't float. Your argument is more like not shooting people who enter your house uninvited. ;-)

Reply to
krw

It's downright trivial to produce an accurate edge transition at the zero crossing, with enough oomph to whack an opto-coupler into producing a sharp edge...

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as I opined in a much earlier post: all it takes is a simple-minded capacitive voltage dropper to power a comparator.

So the remaining question is what kind of pulse do you want to see on the other side of the opto-coupler... positive going at each zero-crossing with what width, or what?

Please define and I'll finish the exercise. ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

I was poking fun of calling you a year or so ago, jut to say hello. :)

--
You can't have a sense of humor, if you have no sense.
Reply to
Michael A. Terrell

Ah, yes! You did call me ;-) ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Perhaps like this...

formatting link

Choice of comparator is left as an exercise for the student... but even a lowly LM339 will do if you can stand the 300ns of extra delay ;-)

Of course Mr. Snotnose, "company president", will say too many parts. ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

Idiot. An LM339 will go nuts from the negative input swing. What did you use to model it, an ideal comparator?

Hey, 17 parts isn't bad, for an amateur. But you'll need to work on it to get it past UL.

--

John Larkin, President       Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com   

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME  analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators
Reply to
John Larkin

Gotcha! But you're too dumb to know why ;-)

The 4N25 probably doesn't meet UL, but there's nothing else any worse than your approach.

You're nothing more than a narcissistic ignorant SOB who constantly needs to be on your soapbox so you can claim adequacy.

Your claim has been denied ;-) ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

[snip]

More on that later. Waiting to see how deeply Larkin will try to immerse his foot in the cow patty ;-)

A colleague reminds me that in 2001 we used a very similar method to power a washing machine controller for Emerson Appliance Controls Division. In fact most of the controller was on the line side of the boundary. I assure you that Emerson got UL approval. ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

LM339 behaves sensibly with inputs as low as -0.6V, it'll need a pull-up on the output though,

--
?? 100% natural

--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net
Reply to
Jasen Betts

John Larkin a écrit :

That one is pretty low count, low power, and need no clean up circuit/soft,...

I don't think there's a mean to save one opto :-(

10n || .---||-------+----. | || | | | V -> | | OPT1 - | | | | | |/ | | .--| z 1K | 220K | |> A 24V ___ | ___ | | | --|___|-+-|___|-+ +----+-----. MAIN | | | | | -. | | |< z | | | '--| A 24V | | | |\ | | | | | | | | | OPT2 V -> | | | | 10n - | | | | || | | | | '---||-------+----' | | || | '------------------------------' 
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Thanks,
Fred.
Reply to
Fred Bartoli

Yes. Under most conditions. And only one input misbehaves even if you suck current out of it.

Yes. ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

No. I'm working with a company right now where _everyone_ is younger than my children... with some even as young as my oldest grandchild. And they are peaches to work with. Seems their professors at RIT used some of my early circuit designs as teaching examples ;-)

And it's no piddling company... they just shipped their BILLIONETH chip! ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
I love to cook with wine.     Sometimes I even put it in the food.
Reply to
Jim Thompson

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