One does not expect to generate a sine wave with –100dBc distortion using a 5V low power op amp. All the same, a bandpass filter using the LTC6258 can combine with an easy-to-use low power oscillator ...
The circuit was designed based on the functionality of an op-amp to create a Wien bridge oscillator to generate sine waves in the frequency range of 15 Hz to 150 kHz that is channeled using four ...
Over on YouTube [Andrew Neal] has a Function Generator Build for Beginners. As beginner videos go this one is fairly ...