A Switched-Capacitor RF Front End With Embedded Programmable High-Order Filtering

摘要

We propose a switched-capacitor radio-frequency (RF) front end achieving an equivalent high-order, tunable, highly linear RF filtering to improve the out-of-band (OB) blocker tolerance. RF input impedance matching, -path filtering, high-order discrete-time infinite-impulse response (IIR) filtering, and down-conversion are implemented using only switches and capacitors in a 0.1–0.7 GHz prototype with tunable center frequency, programmable filter order, and very high tolerance for OB blockers. The 40 nm CMOS frontend consumes 38.5–76.5 mA, achieves 40 dB gain, 24 dBm OB IIP3, 14.7 dBm 1 dB blocker compression point (B1dB) for a 30 MHz blocker offset, 6.8–9.7 dB noise figure, and 66 dB calibrated harmonic rejection ratio.