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    indulis or Audioguru?

    Just because Audioguru hasn't seen one, doesn't mean you can't make one. That's not to say it's "practical to do so"... The theory and equations were given.
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    indulis or Audioguru?

    It would be fair to say this is a subject that I know a "little bit" about, being a DC-DC converter (SMPS) design engineer. Audioguru's statement... is incorrect. My response was... The point is that you don't have to use a transformer (for flyback's its a coupled inductor). Why do you...
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    indulis or Audioguru?

    Hey I'm no genius... what did Audioguru say that was correct that I said wasn't.
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    Why doesn't my inductor give more kick.

    Even my old Eico 5MHz kit scope I built over 30 years ago could do 1KV, so I doubt and newer scope is limited to 100V. Since you didn't want to give these a go... answer: Yes there will be a spike. The di/dt is from the current going from some level to zero. Again it's... V=L*di/dt As time (t)...
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    Why doesn't my inductor give more kick.

    The formula is V=L*di/dt . You need a high di/dt or a very large L. This doesn
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    Why doesn't my inductor give more kick.

    I'd be cautious calling it a zener!! What you said was... Sounds like you used the "transformer" word to me. A non-isolated flyback (or if you like "... a step-up power supply that uses a single Mosfet and only a coil...") can generate a voltage just as high as a converter with a transformer...
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    Why doesn't my inductor give more kick.

    Mr. Klampfer On occasion, some of  "your theories", only "loosely" follow fact, and are not 100% correct... for example: This statement is 100% incorrect. A boost converter (what you call a "stepup" power supply or is know more commonly as a non-isolated flyback) and a isolated flyback...
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    Why doesn't my inductor give more kick.

    AG You may want to review power MOSFET construction and operation (i.e. Miller Effect, and body diodes) and give that explanation another go.
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    What si that series resistor with Diode in and Inductor Switch circuit?

    The diode is there on relay coils to protect the switching device. If someone put a R in series with a diode across a relay coil, it was to limit the current thru the diode. To control rise and fall time's, most common are RC and RDC snubbers.
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    Convert 0-30V 3A PSU to 5A or more

    Audioguru Both of those quotes are yours!! There are better ways to add the reference... Vin may not always be constant.
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    What si that series resistor with Diode in and Inductor Switch circuit?

    Think about it... what makes a "better short", a diode, or a diode in series with a resistor when it comes to discharging an inductor?
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    Convert 0-30V 3A PSU to 5A or more

    and So which is it?? Adding a TL 431 to this circuit is VERY, VERY SIMPLE!!! A1 can even be used as a buffer. Your joking when you say a non-presision, non-temperature compensated zener will work better than a "real reference" ... right??
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    What si that series resistor with Diode in and Inductor Switch circuit?

    You sure you want to stick with this...  (hint: a resistor LIMITS current)
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    motor driver L298 help

    Both of these chips are nothing more than CURRENT drivers for inductive loads. I have to go with Audioguru on this one, in that speed, of a DC motor is controlled by PWM or voltage change (resulting in a current change). Just about every "driver", at least the ones I've seen in DC-DC's are TTL...
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    What is holding switch mode PSUs back?

    A lot of them use POL (point of load) converters to further filter/regulate the voltage or even use an intermediate bus architecture. Nowadays, even digital control is used to set the output voltages of POL's in order to set CPU speed. It's come a long way since "the old days"!! You also have to...
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    What is holding switch mode PSUs back?

    First, sorry for the typo... my XHR 40-25 is 0-40V, 0-25A not 40A, but hey... 1KW is 1KW. The SMPS in a computer is a discontinious mode flyback. The switching edges all ring like hell and the ripple is a bitch to get down. The reason "they" use this topology is that it's "CHEAP" to build (you...
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    What is holding switch mode PSUs back?

    Those who work in the industry have probably heard of a company called Vicor. It was founded by a guy named Dr. Patrizio Vinciarelli... When I was working for LTX,  I was fortunate enough to have had a working relationship with Patrizio and Vicor when in it was in it's infancy (just a bunch of...
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    Heatsink Surface Area

    Thermal conduction and capacity are material related. Thermal "convection" is not. Yes, the copper heat sink will take longer to heat up, but it will reach the same final temperature as the aluminum heatsink
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    Heatsink Surface Area

    The metal is NOT important!! A heatsink of a particular size, whether it's made of copper or aluminum, IS THE SAME!!  Now if you wanted to talk about thermal capacity, that's a different story.
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    Constant current source for a low Ohm load

    What is the purpose of R1 & R5? I don't think you'll get to far without some sort of stable reference... a pot to Vin will not do it. What is the application? It might help in trying to figure out how best to minimize drift!
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