A new two-path band pass Delta Sigma Modulator structure with tunability in filter resonance frequency

This paper presents a new two-path resonator structure which is tunable in resonance frequency. Being able to tune NTF zeros, makes it possible to overcome circuit non-idealities effects on resonator performance. In addition, tunable band pass Delta Sigma Modulator (ΔΣM) can be used in multiband receivers. Using two-path structure leads to more relaxed circuit requirements and low power consumption. Second order ΔΣM using proposed tunable resonator is simulated in both system and circuit level to verify performance. Resonance frequency can be tuned from DC to half of the sampling frequency. Circuit level realization of proposed structure is designed and simulated in 180nm CMOS.