A band stop filter blocks unwanted frequencies while passing others. Learn its types, design tips, characteristics like Q factor and roll-off, and key uses in audio, telecom, and medical devices. Includes analog, digital, and notch filter circuits.

An integrator amplifier uses an op-amp and capacitor to output the time-integrated voltage of an input signal. Learn its working principle, components, design tips, applications, and differences vs. differentiators. Ideal for analog signal processing.