Feedthrough capacitance compensation for resonant devices
US8193869B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 2010 |
| Grant date | Jun 5, 2012 |
| Priority date | — |
| Expiry date | May 4, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B5/36
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A device has a resonator coupled to input and output nodes, the resonator being characterized by a transducer to drive the output node, and further characterized by a feedthrough capacitance such that portions of the input signal bypass the transducer to allow a spurious signal to reach the output node. The device includes a compensation capacitor coupled to the output node to define a compensation capacitance in accordance with the feedthrough capacitance. A phase inversion circuit is coupled to the compensation capacitance to generate a compensation signal and coupled to the output node such that the spurious signal is offset by the compensation signal. In some cases, a differential amplifier of the phase inversion circuit has the compensation capacitance in a feedback path to offset the feedthrough capacitance. In these and other cases, the compensation capacitance and the feedthrough capacitance may be unmatched to avoid overcompensation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.