An inductorless 3–5 GHz band-pass filter with tunable center frequency in 90 nm CMOS

A novel inductorless tunable switched-capacitor band-pass filter based on N-path periodically time-variant networks is presented. The proposed UWB band-pass filter is complete with ring-oscillator used for multi-phase clock generation suitable for power-efficient IR-UWB systems. The filter prototype was fabricated in TSMC 90 nm CMOS, and occupies a chip area of 0.004 mm
²
. It archives a −3 dB bandwidth of 2 GHz while the center frequency can be tuned from 4 GHz to 4.4 GHz. Power consumption is 1.1 mW from 1.2 V supply voltage, and the performance was verified experimentally.