Amplifiers – With semiconductor amplifying device – Including class d amplifier
Reexamination Certificate
2006-06-27
2006-06-27
Nguyen, Linh V. (Department: 2819)
Amplifiers
With semiconductor amplifying device
Including class d amplifier
C330S253000
Reexamination Certificate
active
07068103
ABSTRACT:
An audio preamplifier (10) based on an operational transconductance amplifier, in combination with a class D audio output amplifier (12) is disclosed. The input signal is coupled to the preamplifier (10) through a capacitor (14) in series with a resistor (17) that sets the transconductance of the preamplifier. The preamplifier (10) includes a differential operational amplifier (20) that drives output MOS transistors (22a,22b), which are biased by current sources (24a,26a;24b,26b). Feedback from the drain nodes of the output MOS transistors (22a,22b) to the inputs of the differential operational amplifier (20), along with the series capacitor (14) and resistor (17) input coupling, ensures minimum offset voltage and current at the output of the preamplifier (10). Common mode feedback control amplifiers (25, 29) ensure proper bias of the components into the saturation region.
REFERENCES:
patent: 3530395 (1970-09-01), Prusha
patent: 5594386 (1997-01-01), Dhuyvetter
patent: 5642070 (1997-06-01), Furukawa
patent: 5642076 (1997-06-01), Naokawa et al.
patent: 5838807 (1998-11-01), Andersson et al.
patent: 6118336 (2000-09-01), Pullen et al.
patent: 6127885 (2000-10-01), Colangelo
patent: 6144256 (2000-11-01), Barbetta
patent: 6166596 (2000-12-01), Higashiyama et al.
patent: 6448851 (2002-09-01), McIntosh et al.
patent: 6563377 (2003-05-01), Butler
patent: 6707337 (2004-03-01), Noro
patent: 6762645 (2004-07-01), Grant
patent: 6952131 (2005-10-01), Jeong et al.
Pierce, et al., Applied Electronics (Bell & Howell, 1991). p. 448, no month.
“Data Sheet: TDA8922 2×25W class-D power amplifier” (Philips Semiconductors; Mar. 23, 2003).
“Data Sheet: TDA8920 2×80W class-D power amplifier” (Philips Semiconductors; Sep. 25, 2002).
Geiger et al., “Active Filter Design Using Operational Transconductance Amplifiers: A Tutorial”, Circuits and Devices Magazine (IEEE, Mar. 1985). pp. 20-32.
Grise, “Application of the Operational Transconductance Amplifier to Voltage-controlled Amplifiers and Active Filters”, et.nmsu.edu/-etti/winter98/electronics/grise/wrg.html, no date.
Brady III W. James
Nguyen Linh V.
Telecky , Jr. Frederick J.
Texas Instruments Incorporated
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