Sampled data-biasing of continuous time integrated circuit
US5621355A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1995 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Sep 29, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/04
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Process-dependent characteristics of a continuous time circuit, e.g., particular the sensitivity of the corner frequency of a continuous time filter to variations in absolute capacitance, is obviated by modifying a resistance-based transconductance tuning circuit, so that the tuning resistor is replaced with a switched capacitor circuit. The effect of this switched sampled data resistor replacement is such that, if each of the resistor-simulating switched capacitor of the transconductance stage and one or more load capacitors of the filter is established in the same processing sequence, what would otherwise be process-sensitive terms in the corner frequency-establishing ratio (g.sub.m /C) effectively cancel each other, so that the corner frequency fhi becomes proportional to a readily controlled frequency parameter for the sampled data resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.