This is an existing circuit of buck regulator circuit I have been reviewing with.(Here I have not mentioned the part number of the due to the confidentiality issue)
Following is the screenshot of the feedback resistor design.
Reference voltage of the buck regulator is 1 V and output is designed for 3.3 V . Feedback regulator resistors (51 kΩ , 22.1 kΩ) combination design I have reviewed and verified the values.
Opamp feedback path and its functions are confusing sections for me. Following is my understanding, current feedback across the 100 Ω resistor is taken across to the amplifier input and voltage output comes in parallel with the feedback path ( 22.1 kΩ) through a buffer.
Can anyone suggest the purpose of the opamp-feedback circuit? And what could be possible output voltages at the buffer (op-amp) output.