A leakage current compensation system and method is disclosed that reduces frequency spurs and phase offset in a frequency synthesizer. The leakage current is determined based on the phase offset of the frequency synthesizer relative to a reference clock. A leakage current compensation circuit provides a leakage current compensation signal to the frequency synthesizer at the loop filter terminals to minimize the phase offset.
A method and apparatus for post-fabrication adjustment of a phased locked loop leakage current is provided. The adjustment system includes a programmable current source that adjusts a leakage current offset circuit to compensate for the leakage current of a capacitor. The capacitor connects to a control voltage of the phase locked loop. The programmable current source includes at least one current source and switch to adjust the leakage current offset circuit. The programmable current source is selectively adjusted by a combinational logic circuit. Such control of the leakage current in the phased locked loop allows a designer to achieve a desired phase locked loop operating characteristic after fabrication of the adjustable phase locked loop.
A method and apparatus for post-fabrication calibration and adjustment of a delay locked loop leakage current is provided. The calibration and adjustment system includes an adjustment circuit that adjusts a leakage current offset circuit to compensate for the leakage current of a capacitor. The capacitor connects to a control voltage of the delay locked loop. Such control of the leakage current in the delay locked loop allows a designer to achieve a desired delay locked loop operating characteristic after the delay locked loop has been fabricated. A representative value of the amount of adjustment desired in the leakage current may be stored and subsequently read to adjust the delay locked loop.
A method and apparatus for post-fabrication adjustment of a phase locked loop leakage current is provided. The adjustment system includes an adjustment circuit that adjusts a leakage current offset circuit to compensate for the leakage current of a capacitor in the phase locked loop. The capacitor connects to a control voltage of the phase locked loop. Such control of the leakage current in the phase locked loop allows a designer to achieve a desired phase locked loop operating characteristic after the phase locked loop has been fabricated.
A method and apparatus for post-fabrication adjustment of a delay locked loop leakage current is provided. The adjustment system includes a programmable current source that adjusts a leakage current offset circuit to compensate for the leakage current of a capacitor. The capacitor connects to a control voltage of the delay locked loop. The programmable current source includes at least one current source and switch to adjust the leakage current offset circuit. The programmable current source is selectively adjusted by a combinational logic circuit. Such control of the leakage current in the delay locked loop allows a designer to achieve a desired delay locked loop operating characteristic after fabrication of the adjustable delay locked loop.
A method and apparatus for post-fabrication adjustment of a delay locked loop leakage current is provided. The adjustment system includes an adjustment circuit that adjusts a leakage current offset circuit to compensate for the leakage current of a capacitor in the delay locked loop. The capacitor connects to a control voltage of the delay locked loop. Such control of the leakage current in the delay locked loop allows a designer to achieve a desired delay locked loop operating characteristic after the delay locked loop has been fabricated.
