Building comparator from discrete components?

[mishima]

Hi, I'm interested in building a breadboard version of the simplest comparator using transistors and resistors. Ultimately I'd like to understand the LM393 but looking at the datasheet schematic, it seems quite complicated. I was hoping there was a simpler comparator I could mimic to start out with. Thanks.

 

[mishima]

Like how about this for the 139, it seems more doable/understandable for my skill level:

Is there something even simpler? Or is anything in this circuit not necessary for understanding the comparator action?

 

[NascentOxygen]

A comparator is based on a differential amplifier. See Q10 and Q13. http://www.allaboutcircuits.com/worksheets/diffamp.html

 

[mishima]

Thanks, that's just what I needed!

 

[alphy]

Hi there,

Building a comparator from discrete components is definitely possible and can be a great learning experience for understanding the inner workings of an integrated comparator like the LM393. However, it is important to note that the LM393 is designed to be a highly optimized and efficient comparator, so replicating its functionality with discrete components may not be as straightforward or efficient.

That being said, there are some basic comparator circuits that you can start with, such as the single transistor comparator or the op-amp comparator. These circuits use fewer components and can help you understand the basic principles of comparing and amplifying signals.

However, if your ultimate goal is to understand the LM393, I would recommend studying its datasheet and schematic in more detail. It may seem complicated at first, but breaking it down and understanding each component's purpose can be a valuable learning experience. You can also try simulating the circuit using software like LTSpice to get a better understanding of its behavior.

I hope this helps and good luck with your project!