What is a typical usage/function of this bjt transistor pair configuration with one's base and collector connected?

Thread Starter


Joined Aug 15, 2023
I have been doing a school project in which I need to figure out the working principle of an existing BJT circuit, and then design a corresponding CMOS circuit of the same function and similar performance. Sort of like converting BJT technology circuits to CMOS circuits.
In this picture there's the configuration I've repeatedly seen, but I'm confused about what possible effects/functions it can achieve.
Could anyone give me an idea about what it can do and why we need this structure? (PS: R1, R2 are identical resistor, and T1, T2 are also identical pnp transistor)

Besides, I cannot find enough textbooks or papers on BJT since most IC design guidances are about CMOS circuits only. I am an undergraduate and have zero experience in IC design/analysis. Really don't know where to seek experience. So can anyone offer me some advice? Any books/papers to read that will help my school project(BJT to CMOS technology conversion) or supplement my knowledge on BJT circuits?