A MEMS accelerometric sensor, comprising: - a supporting structure; - elastic suspension elements (8, 9; 98, 99); - a suspended region (2; 62; 92) of semiconductor material, mobile with respect to the supporting structure and anchored to the supporting structure by means of the elastic suspension elements; - at least one first modulation electrode (20; 68; 114), which is fixed to the supporting structure; - a generator configured to bias said first modulation electrode with an electrical modulation signal including at least one periodic component having a first frequency and having a constant amplitude; - at least one first variable capacitor (30; 80; 130), formed by said suspended region and by said first modulation electrode, in such a way that the suspended region is subjected to a first electrostatic force that depends upon said electrical modulation signal; and - a sensing assembly (12, 14, 16, 18, 5a; 12, 14, 16, 18, 65a; 102, 104, 95a) configured to generate, when the accelerometric sensor is subjected to an acceleration, an electrical sensing signal, which indicates the position of the suspended region with respect to the supporting structure and includes a frequency-modulated component, which is a function of said acceleration and of said first frequency; and wherein the suspended region and the elastic suspension elements form a mechanical system, the frequency response of which has a peak at a second frequency; and wherein said first frequency is comprised in the frequency range such that the magnitude of said frequency response is at least equal to the d.c. value of the modulus of said frequency response, increased by 3 dB. - a supporting structure; - elastic suspension elements (8, 9; 98, 99); - a suspended region (2; 62; 92) of semiconductor material, mobile with respect to the supporting structure and anchored to the supporting structure by means of the elastic suspension elements; - at least one first modulation electrode (20; 68; 114), which is fixed to the supporting structure; - a generator configured to bias said first modulation electrode with an electrical modulation signal including at least one periodic component having a first frequency and having a constant amplitude; - at least one first variable capacitor (30; 80; 130), formed by said suspended region and by said first modulation electrode, in such a way that the suspended region is subjected to a first electrostatic force that depends upon said electrical modulation signal; and - a sensing assembly (12, 14, 16, 18, 5a; 12, 14, 16, 18, 65a; 102, 104, 95a) configured to generate, when the accelerometric sensor is subjected to an acceleration, an electrical sensing signal, which indicates the position of the suspended region with respect to the supporting structure and includes a frequency-modulated component, which is a function of said acceleration and of said first frequency; and wherein the suspended region and the elastic suspension elements form a mechanical system, the frequency response of which has a peak at a second frequency; and wherein said first frequency is comprised in the frequency range such that the magnitude of said frequency response is at least equal to the d.c. value of the modulus of said frequency response, increased by 3 dB.