Patent ID: 7352249

Claim:
A phase-locked loop bandwidth calibration circuit, comprising: a programmable charge pump; a phase-locked loop filter operatively connected to said programmable charge pump; an oscillator, operatively connected to said phase-locked loop filter, to generate a frequency signal based upon a signal received from said phase-locked loop filter; and a control loop operatively connected to said phase-locked loop filter and said programmable charge pump; said control loop including a gain measurement circuit, operatively connected to said oscillator, to measure a gain of said oscillator; said control loop controlling said programmable charge pump to adjust its output current level based on the measured gain of said oscillator; said gain measurement circuit including, a voltage difference measurement circuit, operatively connected to said phase-locked loop filter, to measure a voltage difference corresponding to two voltages being output from said phase-locked loop filter at different times, an analog to digital converter, operatively connected to said voltage difference measurement circuit, to convert the measured voltage difference into a digital signal, and a controller to cause said programmable charge pump to adjust its output current level based upon a received digital signal from said analog to digital converter.