Okay, so today I messed around with MOSFETs, specifically looking at depletion mode and enhancement mode. I know, it sounds like a mouthful, but it’s actually pretty cool once you get into it.
First things first, I got my hands on a bunch of different MOSFETs. They look like little electronic bugs, some bigger than others. I remember seeing these things in all sorts of devices, but I never really knew what they did. Turns out, they’re like tiny switches or amplifiers controlled by electricity. Neat, right?
So, I started with the depletion mode ones. These guys are interesting because they’re “normally on.” That means that without doing anything to them, they’re already conducting. To turn them off, I had to apply a certain voltage to the gate, kind of like telling them, “Hey, stop letting current through!” I played around with different voltages and it was fun seeing how the current changed. This felt like a control part.
- Depletion Mode:
- Normally on.
- Need to apply voltage to turn off.
- Fun to see current changes.
Then, I moved on to the enhancement mode MOSFETs. These are the opposite. They’re “normally off,” meaning they don’t conduct unless I apply a voltage to the gate. It’s like giving them the green light to let current flow. I experimented with different gate voltages and it was amazing how they started conducting more and more. I found it is interesting when I pulling an enhancement-mode MOSFET’s gate voltage towards its drain voltage, it turns on.
- Enhancement Mode:
- Normally off.
- Need to apply voltage to turn on.
- Conduct more with higher gate voltage.
I spent the whole afternoon playing with these, measuring voltages and currents, and just seeing what happens. It felt like being a kid again, discovering how things work. I even hooked them up to some LEDs and made them blink. I even hooked them up to other small devices and found that is working as well.
Main Difference
The main difference between enhancement and depletion MOSFETs is pretty simple: one is on by default, and the other is off by default. You need to apply voltage to switch their states. They both have their uses, like depletion mode ones can be used as load resistors in logic circuits.
At the end of the day, I felt like I actually learned something useful. And it wasn’t even that hard! These little MOSFETs are like the unsung heroes of the electronics world, and now I have a newfound appreciation for them. It’s crazy to think how much we rely on these tiny components in our everyday lives.