A 0.75 to 2.2GHz continuously-tunable quadrature VCO

The /spl plusmn/20% tuning range of a fully integrated quadrature LC-VCO is extended to /spl plusmn/50%. The quadrature VCO is inserted in a loop with an SSB mixer and two frequency dividers that add 100/spl times/100 /spl mu/m/sup 2/ area in a 0.13 /spl mu/m CMOS process and draw 10mA from a 1.2V supply. Quadrature error is <2/spl deg/ and phase noise <-120dBc/Hz at 1 MHz offset.