Miscellaneous active electrical nonlinear devices – circuits – and – Specific identifiable device – circuit – or system – Unwanted signal suppression
Reexamination Certificate
2007-10-09
2007-10-09
Le, Dinh T. (Department: 2816)
Miscellaneous active electrical nonlinear devices, circuits, and
Specific identifiable device, circuit, or system
Unwanted signal suppression
C327S552000
Reexamination Certificate
active
10919233
ABSTRACT:
A tuning loop which can tune the cut-off frequency of an active RC filter is disclosed. The cut-off frequency is determined by equivalent resistance and equivalent capacitance in an active RC filter, therefore, the tuning loop changes the equivalent resistance to tune the cut-off frequency. The time constant of the circuit is compared to see if it is equal to the applied preset time cycle after the equivalent resistance value is changed. The cut-off frequency of the filter is tuned to a preset value when the time constant in the circuit is equal to the applied preset time cycle, or the equivalent should be changed until the time constant equal to the applied preset time cycle. A precise result can be obtained after being tuned by tuning loop due to the each component of the tuning loop are operated in an environment which is equivalent to the active RC filter.
REFERENCES:
patent: 5187445 (1993-02-01), Jackson
patent: 5914633 (1999-06-01), Comino et al.
patent: 6677814 (2004-01-01), Low et al.
patent: 6710644 (2004-03-01), Duncan et al.
patent: 6803813 (2004-10-01), Pham
patent: 6842710 (2005-01-01), Gehring et al.
Chen Hung-I
Lou Chih-Hong
Industrial Technology Research Institute
Le Dinh T.
Rosenberg , Klein & Lee
LandOfFree
Frequency tuning loop for active RC filters does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Frequency tuning loop for active RC filters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Frequency tuning loop for active RC filters will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3903087