When resonant pressure sensor is operating

the noise of the sensitive device and the closed-loop interface circuit may cause fluctuations in the output oscillation frequency

resulting in a degradation of the sensor resolution and other performance metrics.A phase noise model for the closed-loop driving circuit of resonant pressure sensor is proposed.On the basis of traditional noise model

the effect of amplitude control loop noise modulated to the vicinity of the resonant frequency through a variable gain amplifier(VGA)on the 1/

f

3

phase noise is taken into account

to predict the sensor noise performance more accurately.Noise contribution of each module of the interface circuit is analyzed based on t

he model

and it is verified through actual circuit testing.This model can be used to predict the phase noise of resonant pressure sensors and provide guidance for the optimization of the noise performance of resonant driving interface circuits.