BDC Motor Phase Current Sense Amplifier Without IC Using only Discrete Componenets

Hi Alhvarez,

I am not an operation amplifier expert. Someone from the general amplifiers team can provide you with more experience help. I'm transferring your question to the GAMPS team. They will reach out to you shortly.

Regards,

Pablo Armet

Hey Alhvarez,

https://www.ti.com/lit/an/sboa285/sboa285.pdf 

https://www.ti.com/lit/an/sboa310a/sboa310a.pdf 

Here are a few discrete amplifier solutions. If you would like to tackle the challenge with a discrete transistor solution, feel free. But you get many advantages of an op amp circuit.

Best,
Jerry

From your point of view, it may have many disadvantages.
Form my point of view, It surely have many advantages.
As wise men say, one man's trash is another man's treasure.
So don't waste your time convincing people about what they don't ask.

Alhvarez,

There are advantages to both discrete transistor and an op amp solution. I was merely trying to provide design resources to help if you chose to go with the amplifier solution.

We currently don't have reference material for a discrete transistor solution. The circuit you shared does seem to be creating some FB voltage based on the output voltage. You can simulate this design in TINA-TI if you would like, to help you decide on the sizing of your resistors for your desired output voltage range. I've linked the download for TINA-TI below.

https://www.ti.com/tool/TINA-TI 

Best,
Jerry

Thanks man this is indeed helpful for me.
I apologize about my answer if its offended you in any way.