Different Operating Regions of Bipolar Junction Transistors (BJTs) | Intermediate Electronics

If the different operating regions of a BJT or bipolar junction transistor ever confuses you or you get them mixed up, you're not alone. Besides having different names for the same regions and names that may seem counterintuitive at first, it's not surprising that it can confuse so many people. We try to demystify this topic by explaining the reasons behind the different names, taking an in-depth dive into a BJT's current/voltage curves, and briefly mentioning the roles each operating region typically fills. If you find this interesting, subscribe to the CircuitBread channel for more videos on beginner and intermediate electronics!

Table of Contents
0:16 Overview of a BJT and how it works
1:51 Overview of the regions
2:29 Breakdown region
3:09 Cutoff region
3:36 Saturation region
4:49 Active region

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[uriyaba]

In 7 minutes and 29 seconds you made me wrap my head around what my professors failed to in 2 semesters. Thank you so much for the video!

[jeromemutuayamukenge]

You just explained my whole semester in 7 mins and 29 secs. Thank you!

[Jess_Atomoxetine]

One of the hardest parts of learning how to use bjts properly, explained in a concise and easy to follow manner, good job.

[yeeguan]

Why this video only has 500 views? It explains BJT very well!

[ding]

Thanks man. Perfect explanation. It would be nice if a large portion of university engineering professors wern't worthless at their jobs.

[billphillips]

Just began to learn about electronics and was building a breadboard circuit that I found in one of the books I have been reading. But have been puzzled for DAYS as to why the circuit I created using a 2N2222 transistor allowed current to flow freely from Collector to Emitter no matter what voltage I put on the Base. After watching your video I now suspect that my Vce is in fact in the Break Down region! You are the first and only one who has pointed this out after researching this issue for days! Thank you!

[tchiksguitars]

I don't get why the other electronics channels get millions of subs and yours is so overwhelmingly underrated! Thanks again !!!

[celestinemachuca]

now I get it >.< agggr in 6 min you just explained a 30 min lecture to me. Thanks

[gwava]

Best explanation of bjt regions ever!!!. Thank you.

[batolurio]

Finally I got it, after taking two times the class and still in the dark, thank you

[willwill]

Excellent with written notes, fabulous!

[manojboganadham]

never understood operation regions this well... thanks a lot!!

[shaneauberger]

Best explanation I’ve seen. Thank you!

[WonderingSoccer]

I finally get idea of the four operation region from the IV curve, before that, I only knew how to draw it with my poor memory, thanks!!!

[viniciusps]

I was struggling to understand these types of regions now I fully understood them. Thank you for the great video :)

[Electronzap]

Active region is confusing alright. Good video!

[zacharyscott]

You should make an addendum to this video covering the reverse/inverted operating region of a BJT.

[magicflour]

i wish i had this during my undergrad intro to circuits class

[adriandeleon]

Love the video! Wish I would've found this channel earlier, better late than never! #subscribed

[amaanabass]

Well explained and very helpful thank you