Patent ID: 8432229

Claim:
Apparatus for generating a signal with a phase locked loop (PLL) having a selected one of a plurality of oscillation frequencies, the apparatus comprising: a multiplexor (MUX) configured to select the signal having the selected one of the plurality of oscillation frequencies based on a control signal; a loop filter configured to provide a tuning voltage based on a feedback loop of the PLL, wherein the loop filter includes a loop filter capacitance; and at least two inductive-capacitive (LC) voltage controlled oscillator (VCO) paths, each LCVCO path coupled between the loop filter and the MUX and having its oscillation frequency set by the tuning voltage, wherein each LCVCO path comprises a LCVCO configured to provide an output signal at one of the plurality of oscillation frequencies, wherein the LCVCO; and a T-gate switch configured to i) couple the associated LCVCO to the tuning voltage when enabled by the control signal to set the LCVCO path to an active state, and ii) insert a relatively high impedance between the capacitance of the loop filter and a capacitance of the associated LCVCO when disabled by the control signal to set the LCVCO path into a dormant state, thereby setting the leakage current of the associated LCVCO to a relative minimal value and maintaining the capacitance value of the loop filter, and wherein the MUX provides an output of the LCVCO path in the active state to provide the signal having the selected one of the plurality of oscillation frequencies.