I found this amplifier circuit. Its a headphone amplifier by Rod Elliot.
What is the purpose of C2L and R3L at the inverting input of the opamp ? Most of the opamp circuits usually only has R3L. This circuit has both the resistor and capacitor together. What does it do ?
Then I found another circuit which also has capacitor and resistor at the inverting input. But this circuit has the capacitor, Ci and resistor Ri flipped.
What is the purpose of C2L and R3L at the inverting input of the opamp ? Most of the opamp circuits usually only has R3L. This circuit has both the resistor and capacitor together. What does it do ?
Then I found another circuit which also has capacitor and resistor at the inverting input. But this circuit has the capacitor, Ci and resistor Ri flipped.