A High Voltage Swing Dual-Band Bandpass $\Delta \Sigma$ Modulator for Mobile Base-Station

A fully integrated high voltage swing dual-band continuous-time bandpass delta-sigma modulator (CT BPDSM) with a high voltage swing and fabricated on a 0.25 μm SiGe BiCMOS is presented. The proposed CT BPDSM consists of a two-stage second-order resonator, a high speed comparator, multi-feedback current DACs, and a high voltage swing driver. The band selection is controlled using a capacitor bank, and fine frequency tuning is conducted by a varactor. At 883 and 955 MHz, the implemented BPDSM with a high voltage swing shows a peak SNR of 40.6 and 41.9 dB, and an error vector magnitude (EVM) of 5.48%, 3.48%, respectively. In addition, it has a differential output voltage swing of 1.55 Vp-p with a dc power consumption of 635.3 mW.