Hello everyone,
I wanted to design a preamplifier for my project. It should amplify 20db in BJT stage (differential amp.) and 40db for opamp stage.
I think I have done the BJT and the buffer stage (first opamp) correctly but at the output of the last opamp (7th pin of opamp) i see a square wave and not amplified as 10 times (20db - 10 times).
Also my teacher says that BJT stage is not totally correct that I need to make some changes for 20db amplifying.
Thank you for your interest.
I wanted to design a preamplifier for my project. It should amplify 20db in BJT stage (differential amp.) and 40db for opamp stage.
I think I have done the BJT and the buffer stage (first opamp) correctly but at the output of the last opamp (7th pin of opamp) i see a square wave and not amplified as 10 times (20db - 10 times).
Also my teacher says that BJT stage is not totally correct that I need to make some changes for 20db amplifying.
Thank you for your interest.