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Math Puzzle...

That's the PLT file. Save it in a separate file with the same name as the ASC file but with the extension PLT. It will plot the desired waveforms in separate panes that give a clear picture of what is going on.

I tried Helmut's version that he gave to JT. It also has strange and wierd window effects even with the max time step set to 1ps and using the .options plotwinsize=0

Here's Helmut's version:

V=(idt(V(x))-delay(idt(V(x)),D))/D

It flattens to a straight line when the time reaches 100ns. If you try different .param settings, such as .param d = 105n, the flat line turns into a semisinusoidal ripple, the same as the original version.

The LC and Bessel filters have none of these problems. Regardless of which version you use and the size of the window, the Bessel filter gives by far the fastest risetime and the lowest ripple.

I think I am done trying to get software averaging to work. For me, the Bessel is the ideal approach. If JT and the others can come up with an averaging method that gives better performance, I'd be happy to take a look. But I don't think they can, and there would always be the concern that it would have some strange response with some signals.

If you have trouble getting this thing to work, I'd be happy to post the whole thing again with the updates.

JK

Reply to
John K
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Sounds like you never met Simpson, either.

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--

John Larkin         Highland Technology, Inc 

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

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

John,

I finally figured out how to add an attachment in ABSE. I zipped the ASC and PLT files and uploaded them to ABSE with the title

"Comparison of 100ns moving average with 100ns RC and 10MHz Bessel filter"

It is set up for Helmut's version - Max Time Step is 1ps with .options plotwinsize=0. It runs slow.

The average turns into a flat line past 100ns.

If you change the Max Time Step to 100ps or the window size to 105ns (.param d = 105n), the average output signal changes to a semisinusoid.

The original version (V=idt(V(x)-absdelay(V(x),D))/D) doesn't need the max time step set to 1ps, and it exhibits the same change past 100ns with the window set to 105ns.

The Bessel and RC filters do not exhibit these effects.

JK

Reply to
John K

AVGX _will_ have ripple... the more cycles included in the window, the less ripple.

Give me some waveforms and I'll run them thru AVG and AVGX and post the results. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   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

Whoosh.

It can use 3 or 5 or by catenation any larger number of points. Just like Bezier curves. Then again, maybe that wasn't in the wiki article.

Plus a lot depends on point density, if you have plenty of points in any interval of interest it works just fine.

Your inability seems to be particular to yourself, i certainly do not share it. I follow Mike's argument, but it is incorrect.

?-)

Reply to
josephkk

It sure wasn't.

A switching regulator input current waveform is a pretty radical thing to fit a

3-point polynomial curve to, or even a 5 point Bezier. What sample interval would you use?

Since you understand how it would work, and I don't, do it and show us.

--

John Larkin                  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

And uphill! Both ways!!! ;-)

Reply to
Michael A. Terrell

In 6 feet of snow and across the C&O tracks (that last part is true :-) ...Jim Thompson

-- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 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

Straight up!

--

John Larkin Highland Technology Inc

formatting link
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

Single line, or multiple? ;-)

Reply to
Michael A. Terrell

Aim for the third rail. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 USA 
+1 845 480 2058 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

Not easy to do with an enlarged prostate, but it might take care of the swelling...

Reply to
Michael A. Terrell

REAL trains, not Eastern wimpy trains. When I was in high school it was still dominated by steam, with diesel just coming on strong. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   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'm from British Columbia--in West Virginia, all the mountains are flat.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 USA 
+1 845 480 2058 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

Indeed, highest point is 5500' (Spruce Knob, near my grandparent's Thompson's farm).

But dz/dx is severe ;-)

...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   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

Monkey Hill, in Audubon Park, is all of 12 feet above sea level. Folks get light-headed up there.

formatting link 

--

John Larkin         Highland Technology, Inc 

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

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

Looks like it has shrunk ;-) ... Google says it's only 4,862', but Prominence is 2,782'

Here's some pictures from up there...

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(His 83rd. He made it to 92)

Beautiful country!

My grandfather kept a couple of cows in a pasture he owned up near the "knob". The farm house, 7th, 6th, 5th photos from last, was in Riverton, WV. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   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 do not have a teaching certificate. It is only high school level math after all.

Oh, and after checking the wiki article it does have extended spans, just not correctly. I don't like the article as it poorly written.

?-)

Reply to
josephkk

My first was a then already old '62 Nash when i was 19. Cost about 150 bucks. And the seats still folded down to make an acceptable bed. Those were some really interesting days.

?-)

Reply to
josephkk

Nice. Sort of like Holland, but with more hanging moss and way, way better food. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 USA 
+1 845 480 2058 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

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