About the "on" resistance of power transistors or MOSFETS related to dissipation and Ohms Law HD

20.02.2022
Second upload. The first video of today was OK, but had a somewhat sloppy calculation, sorry for that. Please read the textbox. Only focus in this video is on the “ON” resistance of a Semiconductor. Be it a MOSFET or a (power) Bipolar transistor, could be NPN or PNP, MOSFET or Bipolar semiconductor. That does not matter regarding these principles. Not talking about Mosfets or Bipolar transistors that are driven with pulses on a certain frequency (AC), say about the duty cycle etc. Is another subject. It is now all about the practical “Ohms” resistance between the Drain and the Source (FET/MOSFET) or the Emitter and the Collector (Bipolar transistor types). In the latter setup (with the bipolar transistor) the standard voltage drop (related to the internal ON resistance in cases of a Silicon transistor) between Collector and Emitter is approximately 0.7-0.8 Volt, due to its physical properties (valence band values). How that works out in terms of heat is visible here https://youtu.be/5E-U5n_bxjE Also: Ohms law in practice https://youtu.be/icTfvjOYgV8 And, especially about MOSFETS: are they ideal in power circuits? (Yes...) https://youtu.be/tlNLtA07VFk Important: the same issues (Voltage Drop issues) appear when we are talking about Chip Voltage Regulators (5-40 Volts). Some Chip regulators have a “Low Drop” voltage mode, say in the 0,2 V – 0,3 Volt range, instead of the 0,7 V-0,8 V voltage drop that is normally present in standard Silicon Semiconductors units. Limitations about this video: I am only talking about the Ohms and the Wattage (laws) in a kind of DC application, testing/talking about standard Silicon transistors and standard MOSFETS and especially on their internal resistance when they are driven into complete saturation via their Base/Gate. Talking about not damaging MOSFETS or Bipolar transistors in such a test situation: a maximum safe positive/negative voltage /current on N or P semiconductors (on their base/gate) is always there. They need a base/gate voltage to get them work properly. Study the datasheet. Regarding MOSFETS: in general only the driver voltage on their Gate is relevant, not (in general) the driver/driving current. They act, in fact, on static charges on their Gate, be it (+

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