Bandwidth calibration of active filter
US7692484B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 2006 |
| Grant date | Apr 6, 2010 |
| Priority date | — |
| Expiry date | Oct 26, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2210/04
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An active RC filter has an op-amp and a biasing circuit arranged to bias the op-amp to set a gain bandwidth product of the op-amp according to a desired pole frequency of the filter. The biasing circuit is operable according to an output of an RC calibration circuit. The op-amp can be an OTA transconductance amplifier, and the biasing circuit can be arranged to maintain a constant product of R and transconductance at an input of the transconductance amplifier. This biasing can help to set the pole frequency more accurately and can thus reduce the need for bandwidth margin to be provided to allow for manufacturing process variations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.