Active power supply filter

Claim 1

A processor comprising: an instruction decoder; a scheduler coupled to the instruction decoder; an execution core including a plurality of execution units; and a timing control circuit coupled to the execution core and the scheduler; the timing control circuit including a phase-locked loop circuit including: a phase detector for generating an output signal that is the function of the phases and frequencies of an input signal and a signal fed back to the phase detector; an amplifier coupled to the phase detector; a voltage-controlled oscillator coupled to the phase detector and the amplifier, the voltage-controlled oscillator providing the signal fed back to the phase detector; and a power supply filter coupled to the voltage-controlled oscillator, the power supply filter including: an RC element coupled to a power supply line for connecting to a power source; and a switch coupled between the power supply line and a control node coupled to the voltage-controlled oscillator, the switch having a control terminal coupled to the RC element, the switch being a source-follower circuit.