| 摘要 |
<p>The frequency synthesiser (1) for implementing a self-calibration method of the invention, comprises a first phase-locked loop and a high frequency access, that comprises a digital-to-analog converter (20) to be calibrated by said method, connected to the second input of a voltage-controlled oscillator. The first phase-locked loop includes a reference oscillator (2), a phase comparator (3), a first load pump (4), a first loop filter (5), the voltage-controlled oscillator (10) connected by a first input into the first loop, a multimodal counter-divider (9) controlled by a modulator (11) and connected to the phase comparator. For the calibration operation, the frequency synthesiser includes a second load pump (14) connected to the phase comparator (3) and a second loop filter (15) in the high frequency access. When the second load pump is actuated, it defines together with the second filter connected to the voltage-controlled oscillator, a second phase-locked loop. A voltage comparator (21) compares the output voltage of the digital-to-analog converter (20) with a voltage on the second loop filter in order to calibrate the gain of the converter when the second phase-locked loop is locked on a predetermined output frequency.</p> |
