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Temperature compensated variable gain amplifier



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Document Number
US Patent 5339046
Issued Date
August 16, 1994
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Abstract
An amplifier for a radio transceiver overcomes the problem of gain being dependent on ambient temperature. Transmission power is matched to strength of a received signal by providing matched dual gate FET amplifier stages in both the transmitter and receiver portions of the transceiver. Changes in gain due to temperature are compensated for by detecting changes in the FET drain current by measuring the source voltage of the amplifier. The FET source voltage is compared to a reference voltage, and the output signal resulting from the comparison is provided as a control signal to one of the FET gates.
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Temperature compensated variable gain amplifier - US Patent 5339046 Drawing
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Number of Claims:
13
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Owner
Qualcomm Inc. (San Diego, CA)
Published
August 16, 1994
Application Number
08/072,303
Filed
June 3, 1993
US Classification
330/277   330/279 330/280 330/281 330/289
Int'l Classification
H03G   1/04   (20060101)   H03G   1/00   (20060101)  
Assistant Examiner
USPTO Field of Search
330/279   330/289   330/280   330/281   330/277  
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Description
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