Multi-bit sigma-delta analog-to-digital converter with reduced sensitivity to DAC nonlinearities
US5329282A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 2, 1992 |
| Grant date | Jul 12, 1994 |
| Priority date | — |
| Expiry date | Mar 2, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M3/438
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A multi-bit sigma-delta analog-to-digital converter (ADC) (40) includes a sigma-delta modulator (41) with a multi-bit quantizer (46) and a digital-to-analog converter (DAC) (47). An output of the DAC (47) provides an error signal of the modulator (41). The quantizer (46) provides a quantized signal having multiple bits ordered from a most-significant bit, to a second most significant bit, to at least one lower-order bit including a least-significant bit. At least two of these bits, including the most significant bit and one of the lower-order bit or bits, are provided as inputs to the DAC (47). The remaining bits are provided as inputs to a prefilter (49), which performs the same transfer function as a comparable multi-bit modulator. A summing device (49) subtracts the output of the prefilter (48) from the quantized signal. A decimation filter (50) resamples the output of the summing device (49) to provide the output of the ADC (40).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.