An important extra note about 11:50 is that you have to be careful of that resistor value depending on the frequency you're operating at. When the transistor activates and the gate capacitance is discharged it is through the very small impedance of the saturated transistor. So it turns on quickly. But when the transistor turns off and the gate charges, it is through the resistor, and the time constant becomes something you have to worry about. The turn off will be slowed down. As you approach an operating period equal to that time constant the gate won't fully charge and the FET won't entirely cut off. It will spend more time in the linear region while cutting off and will warm. At a high enough frequency it will essentially never charge and the FET will permanently stay on. (Assuming a 1nF gate) Basically if it's anything higher than 10kHz I'd go no higher than 10k for a snappy gate response. And lower it as the frequency goes higher. Better yet add a BJT push-pull stage after the level-shifter and then the gate sees a low impedance to both the high and low side. Really that's what I would do for anything 100kHz or beyond. You're gonna reach a point where to keep the gate responsive at cutoff you'll need such a low resistor value that it will begin to stress the transistor. Plus the average current draw of the resistor-transistor branch could become high enough that it will be problematic for the longevity of battery operated devices. However, at the same time, if you're operating on a seconds/minutes/hours timescale and the transistor will be on or off for a long period of time, 1M should be fine.

A great way to remember which way the "arrow" points is this: "NPN" is Not Pointing iN. Then, of course, "PNP" would be just the opposite. Just remember NPN is Not Pointing iN, and then you'll have no trouble remembering......

Nice video! I use the logic-level MOSFETs like the IRLZ44 that can be driven with 5V.

You have a great way of explaining and visualizing things. Making it very easy to understand what is happening. Thank You !

Always interesting and learning at the same time.👍🤓

The common problem on youtube when poeple explain transistors they only explain npn transistors and sometimes whe have a load grounded and only a pnp can be used and the curcuitry is different to have a constant supply of current when used with a battery But you explained both sides of transistors helping us young players

Still loving your videos! Appreciate the detailed explanation on the differences between NPN and PNP, this video and explanation definitely helps! 👍🏻

Great examples!

Thank you. P-FETs make great Reverse Polarity Protectors = Worthy of a video. Would a PNP/3906 pull-up transistor be needed, for a RPP arrangement? Or, use a CMOS PFET?

On N channel substrate is P then gets transformed to N with gate static. Makes sense.

Which makes me ask, "Why the hell ever use a P-Channel mosfet? :)

As shown, under what conditions would the p-Chan’s drain to source diode conduct?

This package cannot dissipate much power. To drive high current, you need to turn it on completely and you need to transition very quickly.

What is the little PCB board that the potentiometer is mounted to, and where can I get one on line?

A question because I don't know the answer. In the example with the arduino, could you not just have a 10k pull up resistor rather than a BJT?

The reverse current protection diode is drawn as a zener, right? Is it ever used that way?

13:01 I am stilla newbie, but I think in your drawing the source should be at the top (so a connection from the middle to the top)?

"Big load"

May you please explain MagAmp theory ?