Hello, I am using a teensy 3.5 analog pins (ADC) to read signals coming from my amplifying circuit. This circuit is designed to amplify very small currents from a photodiode. After testing the alpha prototype (figure attached), i have concluded that this circuit does not do a good job of differentiating small differences in current from the photodiode, meaning it is not accurate enough. To fix this I want to increase the supply to the rails of the op amp, in order to increase the range of amplification (Better gain). But i understand I am limited to what I can read on the ADC (3.3 V). How much can I increase the range on the ADC?
note: This is all on a breadboard, which causes noise