Method and apparatus for an ADC circuit with wider input signal swing
US7221299B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 13, 2005 |
| Grant date | May 22, 2007 |
| Priority date | — |
| Expiry date | Jun 13, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/44
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An analog-to-digital converter (ADC) system that converts an analog input signal into a digital output circuit uses a method of shaping a pseudo-random signal such that the ADC system can be used with input signals having wider swings. The ADC system also includes a quantizer having a comparator offset of less than =/−¼ least significant bit (LSB) in a stage calibrated for gain errors. A method of operating an ADC circuit includes measuring an amplitude and polarity of an input signal voltage and changing characteristics of a pseudo-random signal to ensure that a subsequent stage of the ADC circuit is not saturated. An implementation of the ADC circuit alters the pseudo-random signal based on the amplitude of the input signal such that when the input signal goes close to a positive rail, the pseudo-random signal alternates between a first range, and when the input signal goes close to a negative rail, the pseudo-random signal alternates between a second range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.