Exploring the Inductive Resistor Heater

[lanenal]

According to you, and to Gmeast, this is impossible. So I want your explanation as to how I did it.
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[size=78%]This clearly shows you didn't understand. You were not even able to discern gate current and leakage current.[/size]

[TinselKoala]

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[size=78%]This clearly shows you didn't understand. You were not even able to discern gate current and leakage current.[/size]

DID YOU WATCH THE VIDEO? Apparently not.

You really have no idea what you are talking about. I am showing MUCH MORE CURRENT than "gate current" or "leakage current" flowing through the mosfet from GATE to SOURCE and from GATE to DRAIN. Enough to make a 12 volt light bulb light up brilliantly.

Explain how this is done, since you claim that the mosfet CANNOT pass more than the leakage current. You might also get off your high horse and watch the video where  I switch the mosfet using only the charge from my fingers, illustrating that only a tiny current, providing a sufficient CHARGE, is needed to switch the mosfet. So what is your explanation for the hundreds of milliAmps of current that I show passing through the mosfet's GATE-SOURCE and GATE-DRAIN capacitances?

Come on, Mosfet master, I want to hear your explanation that explains how ONLY 100 nA can pass, yet the bulb will light nevertheless.

[TinselKoala]

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[size=78%]This clearly shows you didn't understand. You were not even able to discern gate current and leakage current.[/size]

I DID NOT MEASURE, NOR DID I ATTEMPT TO MEASURE, either of those currents. What I DID DO, is to show that the Gate-Drain and Gate-Source capacitances are essentially transparent to currents oscillating at the frequencies being used, and that they will easily pass FAR MORE than the 100 nA leakage current.
Your posts are showing more and more that you do not understand the operation of mosfets. "Gate current" applies to bipolar transistors and is different from the gate CHARGE that must be applied at the mosfet gate to turn it on. Gate leakage, for a mosfet, is just that, and in DC conditions the 100 nA figure is reasonable. The current supplied by a highspeed mosfet driver is there to charge the gate fully at high speed in spite of the gate capacitances, which is not properly "gate current" in the same sense as for a bipolar transistor.
It is definitely the case that power from the gate drive circuit can make its way to the load by way of the gate-drain and gate-source capacitances, at far higher currents than 100 nA, and this is what I showed in my video. It's really too bad that you continue to deny what is being demonstrated right before your eyes. Or would be, if you'd actually watch the video.

[TinselKoala]

Does this sound familiar?

This circuit should be the easiest to tune as well (Reason: when the pulse is at 6V, all transistors should be open switch, so logically, there will never be battery shorts). The pulse voltage source V5 can be replaced by a 555 astable circuit. V6 can be obtained by using an equal voltage divider (two 5K resisters, for example) sharing the same power as the 555 circuit. All the JBT transistors can be replaced with equiv. MOSFETs. I used voltage dependent current source and a resistor to mimick the behavior of a transformer. You can use 4 transformers instead in your implementation (MOSFETs are probably better than JBTs, I am affraid, as MOSFETs have no gate current). I used no diodes for switching purpose in this circuit. LTspice simulation is performed and the plot of the current over the load R3 is given below (I omitted the two capacitors at each end of the load R3 for the sake of simulation, in your implementation, you should include them).

Do they, or don't they? Why is a 9 amp driver needed then? Because of the 100 nA leakage?

[poynt99]

Transistors are gated by currents, while MOSFETS are gated by voltage difference, and to develop voltage difference there is a "hidden cap" (so to speak) at the Gate. The current depends on the frequency, max voltage difference, the current limiting resistor, and the capacity of the hidden cap. The gate leakage current is due to the imperfect insulation inside the "hidden" cap.

regards,

lanenal

What happens when the "hidden cap" is getting charged? Is the "hidden cap" between the Gate and GND, or between the Gate and Source and the Gate and Drain?