A 99.2 dB SNDR Feedforward Delta-Sigma Modulator with Build-In Summation Quantizer

A new type of quantizer with build-in weighted summation function is proposed for replacing summer in feedforward delta sigma modulators. To verify the validity, a 2nd-order 8-level modulator based on this quantizer has been implemented in 180 nm CMOS technology. Simulation results show that the modulator achieves a 99.2 dB SNDR in 25 kHz bandwidth while consumes 1.56 mW under 1.8 V supply.