John Xu
Member level 3
dc offset correction
Hi,
I have aquestion on the dc offset loop for a high gain amplifier, e.g., a limiting amplifier.
We know in the high gain amplifier design, we always need a dc offset loop to reduce the mismatch effect. It consists of a low pass filter which is to extract the dc level and feed abck to the input port. I noticed in many designs, there is a amplifire located in this dc offset loop path. Pls. see the attached file, Fig.1.
Can anyone help me to understand the function of this amplifier? Is it to isolate the crosstalk of the input/output? Or it is to isolate the twop poles of the input and feedback loop? Or anyother functions???
Thanks in advance
Hi,
I have aquestion on the dc offset loop for a high gain amplifier, e.g., a limiting amplifier.
We know in the high gain amplifier design, we always need a dc offset loop to reduce the mismatch effect. It consists of a low pass filter which is to extract the dc level and feed abck to the input port. I noticed in many designs, there is a amplifire located in this dc offset loop path. Pls. see the attached file, Fig.1.
Can anyone help me to understand the function of this amplifier? Is it to isolate the crosstalk of the input/output? Or it is to isolate the twop poles of the input and feedback loop? Or anyother functions???
Thanks in advance