How does one select the type of power supply and or topology to use when designing a power supply? Should it be continuous, discontinuous, isolated, non-isolated, voltage mode, current mode, forward, flyback, Cuk, synchronous, non-synchronous, etc., or not even a SMPS at all and a linear instead? The target application and cost as well as other factors dictate/influence the final choice, and each and every one of "them" has advantages and disadvantages... it's all a game of trade-off's!! Consumer electronics tends to focus on cost, hence more profit for the manufacturer, while other areas, telcom, military and hi-rel for example, have different needs… load sharing, or maybe it's low noise, good transient response... etc.
Obviously Audioguru has amassed a great deal of practical knowledge over the years in his career in consumer electronics, I believe... at Philips or was it Panasonic up there in the Toronto area? Don't get me wrong, that knowledge is worth it's weight in gold and many on this forum, as well as others, have benefited from it!!! However, on the basis of statements like
I have never seen a SMPS use a single untapped coil to stepup the voltage of a battery to a high voltage and gave examples of circuits that stepup the voltage not very high. Indulis said I was incorrect but didn't give examples showing why. I have never seen a SMPS use a single untapped coil to stepup the voltage of a battery to a high voltage and gave examples of circuits that stepup the voltage not very high. Indulis said I was incorrect but didn't give examples showing why.
To which I will once again say... just because you ain't seen it, doesn't make it so... and just because I didn't give a "real world" example of "this" circuit in a product you can buy a Radio Shack, still doesn't make it so.
So I said that type of circuit "doesn't stepup the voltage very high" and you say it can but it is impractical so none are made that way?
No I NEVER said "...none are made that way...", I said it may not be very practical to do so (If your gonna quote me at least make sure that it's accurate). Basically, that just means you won't see it in any commercial products, but there may be applications where you may want to make it that way.
Then my statement is not totally incorrect. I should have said, "That type of circuit isn't used to stepup the voltage very high".
Right back to where we started... V=L*di/dt says it all... this is "THE EQUATION" for the voltage across an inductor. If your up on you calculus, take the limit of the function as "t" approaches zero... there's your answer as to high the voltage can go. Sure there are higher order affects that come into play that limit the absolute number, but as a fist order approximation, it is close enough here. So, unless you can prove this formula is wrong, some of your statements are indeed incorrect. If on the other hand I am wrong, please, by all means prove it, but not by saying... show me a product where it's used, and if you can't, then it's not possible. Show me analytically that I'm wrong. Like I said... I'm no genius
