Continuous-time incremental analog-to-digital converter

1. A continuous-time incremental analog-to-digital converter (ADC), comprising:

a plurality of resettable integrators, each integrator configured to convert a sum of signals received at its input to a signal indicative of an integral over time of the sum of signals, the plurality of integrators comprising at least:

a first-stage integrator configured to receive at its input a baseband signal; and

a final-stage integrator configured to produce at its output a final-stage analog signal;

wherein the plurality of integrators are arranged in a cascade configuration such that an output of each of the plurality of integrators other than the final-stage integrator is coupled to the input of a subsequent integrator; and

a feed-in gain element coupled between the input of the first-stage integrator and the input of another integrator of the plurality of integrators, the feed-in gain element configured such that a signal transfer function of the ADC is approximately equal to a signal transfer function of a discrete-time ADC equivalent to the ADC.

2. The ADC of claim 1 , further comprising a quantizer configured to convert the final-stage analog signal to the digital output signal.

3. The ADC of claim 1 , the ADC further comprising a plurality of digital-to-analog converters (DACs), each particular DAC associated with one of the plurality of integrators and configured to convert the digital output signal into a second current-mode signal such that the second current-mode signal is carried to the input of the integrator associated with the particular DAC.

4. The ADC of claim 1 , the feed-in gain element comprising a resistor.

5. A wireless communication element, comprising:

a transmit path configured to convert a first digital signal into a first modulated wireless communication signal and transmit the first modulated wireless communication signal;

a receive path configured to receive a second modulated wireless communication signal and convert the second wireless communication signal into a second digital signal:

a continuous-time incremental analog-to-digital converter (ADC), the ADC comprising:

a plurality of resettable integrators, each integrator configured to convert a sum of signals received at its input to a signal indicative of an integral over time of the sum of signals, the plurality of integrators comprising at least:

a first-stage integrator configured to receive at its input a baseband signal; and

a final-stage integrator configured to produce at its output a final-stage analog signal;

wherein the plurality of integrators are arranged in a cascade configuration such that an output of each of the plurality of integrators other than the final-stage integrator is coupled to the input of a subsequent integrator; and

a feed-in gain element coupled between the input of the first-stage integrator and the input of another integrator of the plurality of integrators, the feed-in gain element configured such that a signal transfer function of the ADC is approximately equal to a signal transfer function of a discrete-time ADC equivalent to the ADC.

6. The wireless communication element of claim 5 , the ADC further comprising a quantizer configured to convert the final-stage analog signal to the digital output signal.

7. The wireless communication element of claim 5 , further comprising a plurality of digital-to-analog converters (DACs), each particular DAC associated with one of the plurality of integrators and configured to convert the digital output signal into a second current-mode signal such that the second current-mode signal is carried to the input of the integrator associated with the particular DAC.

8. The wireless communication element of claim 5 , the feed-in gain element comprising a resistor.