| 摘要 |
A method for shuffling capacitors from period to sample period in a stage of a multi-stage analog to digital converter ("ADC"). The ADC stage includes a plurality of capacitors usable for storage of charge during a sample phase and for providing during an amplification phase, in conjunction with an amplifier, an output signal having a voltage representing the difference between the digital output voltage level for the stage and the analog input voltage level for the stage. The method includes the following steps. First, the input is provided to the plurality of capacitors during the sample phase to capture and hold the first analog voltage level at a first time in the sample phase. Then, a selected sub-group of the plurality of capacitors is used as feedback capacitors, while a remaining sub-group of the plurality of capacitors is used as digital to analog subconverter ("DASC") capacitors, in conjunction with the amplifier, the selected sub-group and the remaining sub-group being different sets in adjacent sample periods. The selection of capacitors is performed in accordance with a predetermined capacitor shuffling procedure adapted to convert resulting harmonic distortion associated with capacitor mismatch into noise having a spectral amplitude peak placed outside of a predetermined spectral band.
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