Differential amplitude controlled sawtooth generator

A dual output differential sawtooth generator, comprising:

• a first dual-capacitor voltage generator circuit configured to provide a positive-going sawtooth output signal;
• a second dual-capacitor voltage generator circuit configured to provide a negative-going sawtooth output signal;
• a comparator circuit configured to compare the positive-going sawtooth output signal with the negative-going sawtooth output signal and provide a comparator output signal;
• a dual charge pump configured to provide feedback control to the first and second dual-capacitor voltage generator circuits;
• and
• a phase frequency comparator coupled to the comparator and the dual charge pump and configured to control the dual charge pump.

A dual differential sawtooth signal generator, comprising:

• a first sawtooth generation means for providing a positive-going sawtooth output signal;
• a second sawtooth generation means for providing a negative-going sawtooth output signal;
• a comparison means for comparing the positive-going sawtooth output signal with the negative-going sawtooth output signal and providing a comparison output signal;
• a charge pump configured to provide feedback control to the first and second sawtooth generation means;
• and
• a phase frequency comparison means for controlling the charge pump.

A method of generating dual differential sawtooth signals, comprising:

• controlling an amplitude of a first sawtooth output signal by charging a capacitor in a first sawtooth voltage generator;
• controlling an amplitude of a second sawtooth output signal by charging a capacitor in a second sawtooth voltage generator;
• comparing the first and second sawtooth output signals and generating a comparator output signal;
• generating a feedback signal from a dual charge pump to the first and second sawtooth generators;
• and
• controlling the dual charge pump with the comparator output signal.