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 ...
An Over-The-Top input stage is shown in Figure 1. At low common modes, the PNPs Q1 and Q2 form a conventional precision differential pair with tail current provided by I1. Figure 1 Over-The-Top Input ...