Mains voltage zero crossing detector with optical isolated output

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Not true.

Hash:

http://en.wikipedia.org/wiki/Hashish

which is measured in grams.


Ganja:

http://en.wikipedia.org/wiki/Cannabis_

which is measured in many ways.

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You can add another voltage source non-coherent with the 60Hz in series with John S's LTSpice file- it doesn't take but a few volts to make your 'circuit' jitter around by half millisecond or so. That's some ZCD. Unless you do something else, it's not worth more than about

4-bits accuracy for any duty cycle control, maybe stick with 3-bits to play it safe.

is

Hide quoted text -

Any zcd will jitter if you add an incoherent source to the AC line signal, unless you use a bandpass filter or PLL or something. The voltage at the zero crossing is... wait for it... zero!

Quit whining and design something better.

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food.- Hide quoted text -

for a

term

For purposes of phase control, zero crossing refers to the fundamental component and not the interference that has no reliable characterization.

I think it requires a password for the shared area that's different from the account password.

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You can't have a sense of humor, if you have no sense.

Use this for the link:

(It's the one you posted earlier)

Ed

Does this work?

Dropbox is wonderful for private use, but it's a little tricky for public stuff.

If using triacs integrate how much you got this time and feed the error back next cycle.

--
?? 100% natural

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

Which brings me to a somewhat related question which has been bugging me for awhile. If anybody would like to take a look, I posted it in ABSE under a thread titled "HP 8116A reset circuit"

Yes!

Grant.

Given the jitter problem under discussion, that doesn't help. Most people just close a slow loop around the ultimate output.

Back in ancient times, we did do the raised-cosine ramp trick to linearize the transfer curve, namely make the gate timing vs loop error relation nonlinear to compensate for the sinewave shape. That helps control loops a lot.

OK, what I did was view the "public" image and copy the URL. That doesn't work with Dropbox. What I need to do is have it explicitely generate a "public URL", a separate step.

Grrrrrr.

Disco lighting from my past ;-)...

...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.

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Hide quoted text -

Sez you.

--

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

You know, the idea of a zero crossing opto-coupler, if that is what you're trying to imply is to not allow it to switch on at any time until the Line side is at or near the base line, then, if the gate switch is present, it'll allow a turn on, other wise, what you have there, can simply fire off any time.. basically...

Jamie

What I get a kick out of is the "maybe you should try heading home"

Jamie

The output is a cmos-compatible, 60 Hz square wave that is aligned with the AC sine wave. Downstream logic can do whatever it wants with it.

It does what it does.

--

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

VCC | | 100K | +---+---- cmos logic out | | AC-------100K-----180nF------+----+ c | | | b === 1n | | e | A K ===> | | K A +---+ | | | | | | c | AC---------------------------+----+ b === 1n e | | | +---' | gnd

--
?? 100% natural

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

What do you call that, "A brainless hip shot" ?:-) ...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.