Auxiliary input for analog-to-digital converter input charge
US10541702B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2018 |
| Grant date | Jan 21, 2020 |
| Priority date | — |
| Expiry date | Sep 26, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/1245
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Input stages for an analog to digital converter wherein charge for charging parasitic capacitances in the input stage, and particularly in the input switch is sourced from a node which means that it does not have to pass through the input RC filter. This has the effect that the input RC filter can be of lower bandwidth, and/or have a larger resistor value, with the consequent result that there is lower power dissipation in the ADC drive circuitry. In one example this effect is realized by providing a separate input into which charge to charge the parasitic capacitances can be fed from external circuitry. In another example an operational amplifier having high (ideally infinite) input impedance can be used to feed charge to the input switch from the input to the RC filter, or from the node between the resistor and capacitor of the filter, again without unsettling the filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.