Talk:Cockcroft–Walton generator

Charge pumps

Charge pumps are fairly complex devices made with a DC-AC converter (something like this) and another stage (something like this or something inductor/capacitor based). Essentially charge pump is the commercial name for small DC-DC converters and here are some examples. -- Femmina 21:41, 2 April 2006 (UTC)

The article says "The CW circuit, along with other similar capacitor circuits, are often called charge pumps".

After reading Wikipedia articles on voltage multipliers and charge pumps my understanding is that voltage multipliers have AC input and DC output. Charge pumps have DC input and DC output. If the Greinacher/Cockcroft–Walton is classified as a "an electric circuit that generates a high DC voltage from a low voltage AC or pulsing DC input" then it cannot be called a charge pump but it should be called voltage multiplier.

ICE77 (talk) 01:21, 20 August 2015 (UTC)

I think the Charge pump article has too limited a definition, as WP articles on circuits often do. For example, the term "charge pump" is also used in smart card and RFID design for a diode capacitor multiplier that generates the higher DC voltage needed to power the chip from the low RF (AC) voltage from the antenna: [1], [2]. Looking at all electrical usage of the term, [3], [4], [5], [6], [7], it is clear that the term refers to a diode-capacitor ladder network that uses an AC or pulsed current to generate a higher DC voltage by charging capacitors in series, "pumping" charge in one direction, while discharging them in parallel, of which the Greinacher/Cockcroft–Walton circuit was the earliest example: [8], [9] --Chetvorno^TALK 03:37, 20 August 2015 (UTC)

Schematic

It would be good to have a schematic/circuit diagram. The text doesn't convey the simplicity of the scheme. Sangwine 20:54, 17 November 2006 (UTC)

I agree.

Atlant 20:58, 17 November 2006 (UTC)

Impulse generator

Is this device also known as an "impulse generator"? Whogue 02:45, 12 April 2007 (UTC)

Villard circuit

Is this device also known as "Villardschaltungen" in german (english "Villard circuit")? —Preceding unsigned comment added by 62.153.69.41 (talk) 09:30, 3 April 2009 (UTC)

The German wiki article de:Hochspannungskaskade gives Villard-Vervielfacherschaltung as an alternative term. My German is not too wonderful but my understanding of the article is that Villard-Schaltung means a single stage of the multiplier - ie a voltage doubler. In fact, Villard circuit is a misnomer for any of these circuits as I explained in the voltage doubler article. The circuit invented by Villard was just the diode clamp cell of the circuit. The diode clamp followed by a peak detector cell is actually due to Greinacher but is commonly described as a Villard circuit. SpinningSpark 11:22, 3 April 2009 (UTC)

I was also confused by this naming issue. The German article speaks of them as synonyms now but in google scholar I could very little early (<1990) references to "Villard multiplier" (only a patent of French origin that spoke of a Villard-chain) so in my opinion Villard-multiplier is incorrect. -Carpentidge- 16:59, 3 June 2014

We don't really care very much what German Wikipedia has to say. The final arbiter is what is written in reliable sources. SpinningSpark 18:07, 3 June 2014 (UTC)

Possibly Incorrect Schematic

It appears that the SVG version of the image "A simple two-stage CW multiplier" currently showing on this article has half of the diodes pointed the wrong way. I found an older PNG version of the same image with them pointing at what I believe is the correct way.

Old, Possibly Incorrect New, Corrected SVG Version

Older PNG Version

SoCo cpp (talk) 00:11, 27 March 2013 (UTC)

That is a recent change. Reverted for now. SpinningSpark 00:49, 27 March 2013 (UTC)

The older version is definitely correct. see http://www.blazelabs.com/e-exp15.asp and http://www.electronicspoint.com/voltage-multipliers-t222870.html for examples. --Guy Macon (talk) 04:22, 27 March 2013 (UTC)

The Russian Wikipedia has the same error:

https://ru.wiki.x.io/wiki/%D0%9E%D0%B1%D1%81%D1%83%D0%B6%D0%B4%D0%B5%D0%BD%D0%B8%D0%B5_%D0%92%D0%B8%D0%BA%D0%B8%D0%BF%D0%B5%D0%B4%D0%B8%D0%B8:%D0%9F%D0%BE%D1%81%D0%BE%D0%BB%D1%8C%D1%81%D1%82%D0%B2%D0%BE#Cockcroft.E2.80.93Walton_generator

Looks like we need to upload an image to commons to fix it -- probably should be an svg image. --Guy Macon (talk) 06:31, 27 March 2013 (UTC)

Frankly, I'm getting a little tired of this campaign to wipe out png diagrams. So often the replacement diagram achieves nothing other than a larger file, introduced errors, and a poorer look than the original perfectly servicable diagram. SpinningSpark 12:53, 27 March 2013 (UTC)

Sorry, perhaps I have dislexia, but the both the circuits on this page look the same, and the circuit on the Russian page looks the same as them. Are you saying they are all incorrect? --Chetvorno^TALK 20:00, 1 July 2013 (UTC)

It seems to me that the two drawings on this page are correct. In order that the capacitors all charge in the same direction, the diodes all have to point left (cathode toward the left) for a positive output (for negative output they have to point toward the right) --Chetvorno^TALK 20:11, 1 July 2013 (UTC)

See https://en.wiki.x.io/wiki/File:Cockcroft_Walton_Voltage_multiplier.svg#filehistory

On 13 April 2013 the incorrect image was corrected, making the post above that used to show one wrong schematic and one correct schematic start showing two correct schematics. I assume that someone corrected the Russian page as well. --Guy Macon (talk) 20:14, 1 July 2013 (UTC)

I just picked up on that. Thanks. --Chetvorno^TALK 20:16, 1 July 2013 (UTC)

I just checked the Russian Wikipedia, and they use the same Wikimedia commons image we do, so the correction fixed that page as well. --Guy Macon (talk) 20:54, 1 July 2013 (UTC)

Remove reference to Blaze Labs Research

Blaze Labs is an independent researcher who does not use peer-reviewed journals to publish. I am unaware of any verification of their experiments through peer review or an independent body trying to replicate these results. [10]Nasageek16 (talk) 06:10, 20 March 2017 (UTC)

Looks like pseudoscience to me. I say remove it. --Guy Macon (talk) 07:14, 20 March 2017 (UTC)

Error in multistage double formula:

It reads now "The output voltage is twice the peak input voltage multiplied by the number of stages N " There is am error here in the multistage double formula: the double pro stage leads to 2 to the POWER of N times the initial voltage swing as total resulting voltage instead (2x2x2x....) of 2 TIMES N times the initial voltage swing. The formula should read V =2^N*V0 2A02:1811:CE10:D500:464:8C75:B63F:4DBF (talk) 09:25, 29 July 2017 (UTC)

No; each stage does not double the voltage from the previous stage, it only adds a fixed voltage $V_{\text{P-P}}$ to it. If you read the article's description of how it works you will see that each capacitor is charged to $V_{\text{P-P}}=2V_{\text{in,peak}}$. In an N stage multiplier there are N capacitors in series between ground and the DC output terminal, thus the output voltage is $V_{\text{O}}=2NV_{\text{in peak}}$ Chetvorno^TALK 02:51, 30 July 2017 (UTC)

Might I be so bold as to recommend this video?[11] --Guy Macon (talk) 03:43, 31 March 2019 (UTC)

experiment

This is a good article on the voltage multiplier that C-W used for their experiment, but there should be, somewhere, an article on the experiment itself. That is, the accelerator, what they did with it, and how it works other than the parts described here. Gah4 (talk) 01:33, 11 February 2022 (UTC)

Doubler

Seems to me that the usual voltage doubler is the lowest order of CW. Recent edit summary seems to indicate that those are used in microwave ovens, but don't count. Also, it doesn't matter where the ground symbol is, the circuit works the same way. Gah4 (talk) 13:05, 19 December 2023 (UTC)

Possible error

Hello. This article says that pulsed dc can be used as the input for a Cockroft-Walton generator, but I think that pulsed dc would have to be converted into ac in order to power a Cockroft-Walton generator as described in this article; https://www.researchgate.net/publication/224113935_High_voltage_Switch_Mode_Power_Supply_for_Laser_System.

Is this an error? Mawiokawt (talk) 19:03, 15 August 2024 (UTC)

It seems to me the circuit will work with either a sine wave or square wave input; the essential characteristic is that the waveform must have both positive and negative voltage peaks: (+V_i, −V_i, +V_i, −V_i,... ) it won't work with pulsed DC biased at zero, with zero volts between the pulses: (+V_i, 0, +_i, 0,... ) This is because alternate diodes are forward biased on alternate half cycles, so for current to flow all the way up the stack it must have both positive and negative peaks. --Chetvorno^TALK 01:52, 16 August 2024 (UTC)

I agree. This would be an example of ac as the current would change direction. A dc current would not change direction. Mawiokawt (talk) 08:27, 16 August 2024 (UTC)