ADC
US8436759B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 2009 |
| Grant date | May 7, 2013 |
| Priority date | — |
| Expiry date | Jan 17, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/466
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
This invention relates to Analog to Digital Converters (ADC) and, inter alia, to Time Interleaved ADCs and Successive Approximation Register (SAR) ADC's. In a conventional Time Interleaved ADC employing SAR ADC units, the input signal is processed through a track-and-hold circuit (T/H), and then through a buffer circuit, before the SAR ADC unit. There, by means of a comparator, the signal is compared with a Digital-to-Analog Converter (DAC) signal from the SAR logic. The buffer reduces the influence of capacitive loading and physical layout design on the SAR ADC input, but typically has a non-linear response and thus introduces distortion to the input signal. This can limit the ADC linearity, particularly for high-speed ADCs operating with low-supply voltages. An objective of the invention is to reduce or eliminate the effect of the buffer non-linearity. This is done in some embodiments by routing both the signals to the comparator through the same buffer circuit. In another embodiment the DAC signal is routed through a separate second buffer circuit. By use of a single buffer circuit, or where there is ideal matching of the buffer circuits in the latter embodiment, the distortion …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.