Patent ID: 7411467
Filing Date: 2008-08-12
Classification: H03B

Abstract:
1. An automatic calibration system for an overtone crystal oscillator, the overtone crystal oscillator having at least one programmable parameter for adjusting closed-loop frequency response of the overtone crystal oscillator and an oscillation node that oscillates upon oscillation of the overtone crystal oscillator, said automatic calibration system comprising: a calibration control circuit which adjusts said at least one programmable parameter through each of a plurality of steps associated with frequency bandwidth; and a sensor, for coupling to the oscillation node of the overtone crystal oscillator, which detects whether the overtone crystal oscillator achieves oscillation at any one of said plurality of steps; wherein said calibration control circuit delays in each of said plurality of steps for a sufficient amount of time to determine whether oscillation is achieved and terminates calibration as soon as oscillation is determined to be achieved.