A tunable 0.5-1.3 GHz CMOS 2nd order bandpass filter with 50/spl Omega/ input-output impedance matching

In this paper, a high Q tunable 2nd order band-pass filter, working in the RF frequency range and designed in a standard AMS 0.35mum CMOS technology, is proposed. The filter is based on three different stages that perform the input and output impedance matching, the bandpass function and prevent instabilities; therefore, it is suitable for integrated front-end RF applications. Simulation results have shown a tunable range between 500 MHz and 1.3 GHz with good input and output impedance matching and a low noise figure. Moreover, this circuit presents a compression-point level higher than -22dBm and a quality factor Q higher than 60