Patent ID: 7639757

Claim:
A drive circuit for a micromechanical resonator, which has at least one pulse modulator for conversion of a complex input signal to a pulsed signal, and which has: a subtraction stage which produces a control error signal from the difference between the complex input signal and a feedback signal; a signal conversion stage, which converts the control error signal to a control signal; a first multiplication stage, which multiplies the control signal by a complex mixing signal oscillating at the frequency ω 0 , and thus produces at least one of a real part and an imaginary part of a control signal which has been up-mixed by ω 0 , a quantization stage, which quantizes at least one of the real part and imaginary part of the control signal which has been up-mixed by ω 0 and thus produces the pulsed signal, with the pulsed signal which is produced by the at least one pulse modulator being used for electrostatic oscillation stimulation of a resonator, and with the pulse modulator being operated at a sampling frequency ω A which is 2 to 1000 times higher than the mixing frequency ω 0 , a feedback unit, which uses the pulsed signal to produce the feedback signal for the subtraction stage, said first multiplication stage having a first multiplier for the in-phase signal path and a second multiplier for the quadrature signal path, with the first multiplier multiplying the real part of the control signal by the real part of the complex mixing signal oscillating at the frequency ω 0 , and thus producing a first result signal, and with the second multiplier multiplying the imaginary part of the control signal by the imaginary part of the complex mixing signal oscillating at the frequency ω 0 , and thus producing a second result signal; and the pulse modulator has an adder which adds the first result signal from the first multiplier and the second result signal from the second multiplier to form a sum signal in order to determine the real part of the up-mixed control signal.