Talk:Split-pi topology

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Energy (Rated Start-class, Low-importance)
WikiProject icon This article is within the scope of WikiProject Energy, a collaborative effort to improve the coverage of Energy on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Low  This article has been rated as Low-importance on the project's importance scale.
 

I'm an amateur electronics hobbyist. I've been messing with electronics less than two years. And yet I came up with this exact topology. How can you patent something so obvious? I thought patents had to be non-obvious.

  • Patent need only to be accepted by the patent office. Then you have to go to trial to demonstrate the obviousness of the patent :/ The topology looks like a cuk design with more switch and a switch to replace the diode.

This topology also appears in 'Advances in Switched-Mode Power Conversion Part I', by Cuk and Middlebrook, dated February 1983.

I think there's quite a lot of marketing going on here. There is no inherent reason this topology is more efficient than any other synchronous buck/boost converter, especially not when there is always an additional MOSFET in the circuit contributing to I^2R losses. —Preceding unsigned comment added by 137.222.189.99 (talk) 09:32, 12 August 2009 (UTC)

Infinite voltage[edit]

I've tried putting a fact check on this before, but Sounddezign reverted it. What's with the "infinity" voltage? I've read the patent, and the inventor claims that in "up-convert" mode, the voltage ratio is equal to the ratio of (t1+t2)/t2, where t1 is the on time of S1 and t2 is the on time of S2. Of course if t2 is 0, then the output would be disconnected from the input. Alternatively, t1 >> t2, but that just means V3/V1 >> 1, not V3/V1 -> inf. I've reworded for now, but I really think this whole article needs some serious looking at. --W0lfie (talk) 18:46, 2 October 2009 (UTC)

A lot of boost switchers produce the "infinite" voltage if they have no load and no feedback. The output rises until the dissipation equals the energy being put in. The inductive kick energy may go to the capacitor or be lost in the inductor if the capacitor voltage is high enough. This unloaded unregulated situation is undesirable and generally not allowed. I was surprised to find out how unstable the output is with a variable load and no feedback. 10/31/12 C.P.

Importance[edit]

The warning labels on top are funny sounding: "it seems too technical and confusing and we don't understand the importance of it"

Yes, the article is important, as someone noted: it is the generalized buck-boost converter by none other than the inventor of the principle. IBM and Linear Technology literature goes to great lengths how life was so hard before these advanced topologies came into existence.

Consider the SEPIC topology. It's been hiding for about 50 years before it became ubiqutious few years ago. Which means that you would had it have most likely "scheduled for deletion" in 2005.

Split-pi topology exists and has very meaningful use in applications where you need to convert power BOTH WAYS at variable ratios. Just because this application isn't common these days, or that there aren't any common control ICs for it today doesn't mean that some crazy heads at LTC or other top power IC companies won't come with one or two. They have been doing it for years, coming with unimaginable solutions, that become commonplace after a few years. SEPIC is an example.

Some "wise" wikeipedia editor recently deleted an important historical part of an ECL logic article, after I criticised the part and the discussion to it; a while later I found the sources to that part with even more explanation that made it all clear and sound. It was about the death of ECL logic and advance of CMOS technology, it happened in about 6 months: CMOS made the ECL utterly obsolete that fast. The source (a man who worked IN THE DESIGN of those powerful CPUs) then compared pictures of both ECL and CMOS solutions and their power envelopes... I wanted to add it to the ECL history part, but it was already deleted from wikipedia, so there... The ECL/CMOS story is important lesson in every electronics engineering book worth its solder. Yet, it was deleted here on the basis of confused discussion in the Talk section. I thought that Talk section is here to bring some clarification or insight into topics. I think it shouldn't be used for nuclear policing. — Preceding unsigned comment added by 178.143.131.98 (talk) 21:50, 2 September 2016 (UTC)

In this case the "Split-Pi" is just the cascade of two more fundamental converters - i.e. a boost and a buck. Understanding those converters gives adequate understanding of this arrangement. I would argue that this doesn't deserve a separate page. Just because there is a patent doesn't mean it has a unique concept. The patent dates from well after cuk and middlebrooks' review of possible converter topolgies — Preceding unsigned comment added by Kcobley (talkcontribs) 14:45, 24 March 2017 (UTC)