A Simplified Gm - C Filter Technique for Reference Spur Reduction in Phase-Locked Loop

Resumen

This paper presents a wideband approach for L5 and S-band integer-N phase-locked loop (PLL) targeting Indian Regional Navigation Satellite System (IRNSS) applications. A reference spur reduction technique using a ????-?? G m - C filter is proposed. The reference spur is improved by 7 dB when compared with one without any ????-?? G m - C filter. The wideband integer-N PLL is designed and fabricated in UMC 65-nm CMOS process. The ????-?? G m - C filter block consumes 200 µ µ A current. The wideband voltage-controlled oscillator (VCO) oscillates from 1.6 1.6 GHz to 3.2 3.2 GHz having a tuning range (TR) of 40% 40 % , achieving a best and worst phase noise of ?-122 dBc/Hz and ?-116 - 116 dBc/Hz at a 1 MHz offset, respectively.