Amplifiers – With semiconductor amplifying device – Including differential amplifier
Reexamination Certificate
2006-08-29
2008-09-30
Pascal, Robert J. (Department: 2817)
Amplifiers
With semiconductor amplifying device
Including differential amplifier
C330S069000
Reexamination Certificate
active
07429893
ABSTRACT:
A variable gain amplifier, VGA, and related method are provided. A reference current variably controlled by a control signal is provided, then the reference current is divided to a load current and an input-control current according to differential driving between a constant reference signal and the control signal. Then the input-control current and the load current are used to respectively bias an input stage and an active load of the VGA, such that a gain of the VGA is controlled by a ratio between the input-control current and the load current. In this way, the gain can be controlled by the control signal. The VGA can provide wider gain range and better variable gain characteristics because a sum and a difference of the input-control current and the load current are both controlled by the control signal.
REFERENCES:
patent: 4528516 (1985-07-01), Hill, III
patent: 5717360 (1998-02-01), Vu
patent: 5896063 (1999-04-01), Marsh
patent: 6566951 (2003-05-01), Merrigan et al.
patent: 6788144 (2004-09-01), Honda
patent: 582137 (2004-04-01), None
patent: 225729 (2004-12-01), None
P. Huang, L.Y. Chiou, C.K. Wang,“A 3. 3-V CMOS Wideband Exponential Control Variable-Gain-Amplifier”, May 1998, pp. I-285˜288, IEEE International Symposium on Circuits and Systems.
Hsu Winston
Nguyen Khiem D
Pascal Robert J.
VIA Technologies Inc.
LandOfFree
Variable-gain amplifier and related method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Variable-gain amplifier and related method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Variable-gain amplifier and related method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3970746