Pipeline type analog to digital converter including plural series connected analog to digital converter stages
US5629700A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1995 |
| Grant date | May 13, 1997 |
| Priority date | — |
| Expiry date | Nov 2, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/167
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An A/D converter block A/D1 converts an analog input signal Vin to a digital signal and outputs its D/A output. First SH/SUBT7, 8 sample the signal Vin and a voltage VRM at the same timing with said A/D conversion and output the results of subtraction of the respective sampling values and the D/A output during holding, respectively. The both results of subtraction are several tens mV and there is no need of taking account of the linearity of a differential amplifier DIFF11. During the sampling, a circuit SHR1 outputs the differential voltages between each reference tap voltage taken out from specific 2 points of the ladder-type resistor in the A/D converter block A/D1 and the voltage VRM while a differential amplifier DIFF12 applies the reference voltages to the next A/D converter block A/D2. Such operations are performed in each stage. Thus, it becomes possible to make any S/H circuit and amplifier of excellent linearity in the first stage unnecessary to reduce the electric power consumption.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.