I am trying to amplify a 0.4Vpp audio signal to 1Vpp using
OPA344 however my output is clipping around 0.5 volts even though my supply is 3.3v
Op-amp is in inverting configuration:
blue trace is input, yellow is output.
[UPDATE]
Fixed – However I'm considering putting the voltage divider on the output so changing the gain won't change the bias
Updated the schematic, this puts me at 1Vpp with a 500mv bias:
Best Answer
As @Transistor says, you need to put a resistor divider on the positive input of the op amp to bias it to 1.65 volts, so your signal can swing positive and negative about this point. The larger problem is that the negative input is a virtual ground, and by using 220 nf and 1K, your output time constant is 220 usec. You have created a high pass filter around 4500 hz (nothing but high audio will get through). Perhaps you should also consider a non-inverting amplifier.