Design of Continuous-Time Σ∆ Modulators with Sine-Shaped Feedback DACs
نویسندگان
چکیده
This work presents a general method to design continuous-time Σ∆ modulators with sine-shaped feedback DACs. A discrete time to continuous time transformation technique is used to compute the continuous-time loop filter coefficients, taking into account the sinusoidal feedback. Examples of high order lowpass and bandpass continuous-time Σ∆ modulators are given as an illustration for the proposed design method. A transistor level sine-shaped feedback DAC is also proposed and compared to a recent circuit design. Finally, the sensitivity of these circuits to clock jitter is studied and compared to the traditional rectangular feedback pulse.
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تاریخ انتشار 2005