Fully integrated fractional PLL for Bluetooth application

A fully integrated sigma-delta fractional-N frequency synthesizer for Bluetooth application is presented. The synthesizer, suitable to be used with a wide range of crystal oscillators, features a settling time of 70 /spl mu/s, a phase noise of -80 dBc/Hz and -125 dBc/Hz at 100 KHz and 1 MHz offset respectively. The fractional spurs are -63 dBc at 1 MHz offset. The synthesizer is part of a 0.13-/spl mu/m CMOS single-chip application for v1.2 Bluetooth, which has been fully qualified between -40/spl deg/C and +85/spl deg/C.