Patent ID: 7075995

Claim:
A three-order sigma-delta modulator, comprising: an analog-to-digital converter, to output a digital modulation signal; a digital-to-analog converter, to convert the digital modulation signal into an analog signal and generate a feedback signal; a first integrating network, to receive an external signal and the feedback signal and generate a first output signal with a first gain factor; a second integrating network, connected in series with the first integrating network, to receive the first output signal and a feedback gain signal with a feedback gain factor that is generated by increasing the gain of the feedback signal by the feedback gain factor, and to generate a second output signal with a second gain factor; a third integrating network, connected in series with the second integrating network, to receive the second output signal and generate a third output signal with a third gain factor; and an adder, connected in series with the third integrating network, to combine a feedforward output signal with a feedforward gain factor that is generated by increasing the gain of the first output signal by the feedforward gain factor and a modulation output signal with a modulation gain factor that is generated by increasing the gain of the third output signal by the modulation gain factor, and to generate a desired noise transfer function.