A Tunable Switched-Capacitor 2-Way Power Divider Based on N-Path Filters

This paper introduces an inductor-less 8-path twoway power divider that is realized by sequentially activating N two-port 2:1 switched-capacitor dc-to-dc converters via N nonoverlapping clock phases. Specifically, each path in the proposed widely tunable power divider splits input power between the two output ports by connecting two capacitors in series across the input port in one phase, which stores half of the average input voltage across each capacitor, and in the next phase, each capacitor is connected separately to an output port. Simulation results of a 65nm CMOS design demonstrate an excellent input and output impedance matching capability, an insertion loss below 2.8 dB, and a power consumption below 54 mW over a tunable range of 0.2 to 1.4 GHz. The amplitude (phase) imbalance is less than 0.3 dB (3°) over the range. The simulation results of IIP
2
, IIP
3
, and OP
1
-dB are 48.1 dBm, 15.8dBm, and 0.78dBm, respectively, and the noise figure is 3.1 dB, at 1 GHz center frequency.