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US5216379A Expired / Lapsed US ⏱️ 0.0 years remaining

Dynamic bias amplifier

Assignee: Individual
•
Filing: 1992-06-26
•
Granted: 1993-06-01
•
Expires: 2012-06-26
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Abstract

Abstract The bias level of an amplifier is controlled by an active bias circuit. The active bias circuit establishes a predetermined amplifier bias level (such as class A mode) as a function of input signal level and load impedance. The load impedance value may be manually entered or determined automatically by a disclosed impedance measuring system. Power supply circuitry is responsive to the value of load impedance to vary the bias voltage applied to the amplifier's output devices.

Inventors

  • 👤 James P. Hamley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 15:02
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/02; H03F1/0205; H03F1/0261; H03F1/0272; H03F1/0266; H03F3/00; H03F3/04; H03F3/08; H03F3/085; H03F3/30; H03F3/3001; H03F2203/00; H03F2203/30; H03F2203/30066

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 102 words
An amplifier comprising: an input adapted to receive an input signal; an output adapted to be coupled to a load; amplifying means for amplifying an input signal received at said input and coupling said amplified input signal to said output; and bias control means including: input signal responsive means for producing a first control signal which is predeterminedly related to a received input signal; impedance responsive means for producing a second control signal predeterminedly related to the impedance of said load; and control means responsive to said first and second control signals for predeterminedly controlling the bias level of said amplifying means.
Claim 2
Dependent Claim 102 words
An amplifier comprising: an input adapted to receive an input signal; an output adapted to be coupled to a load; amplifying means for amplifying an input signal received at said input and coupling said amplified input signal to said output; and bias control means including: input signal responsive means for producing a first control signal which is predeterminedly related to a received input signal; impedance responsive means for producing a second control signal predeterminedly related to the impedance of said load; and control means responsive to said first and second control signals for predeterminedly controlling the bias level of said amplifying means.
Claim 3
Dependent Claim 30 words
The amplifier of claim 1 wherein said input signal responsive means comprises peak detector means for producing said first control signal responsive to the peak value of an input signal.
Claim 4
Dependent Claim 38 words
The amplifier of claim 2 wherein said impedance responsive means comprises: means for manually entering an input corresponding to the impedance of said load; and means for producing said second control signal responsive to said manually entered input.
Claim 5
Dependent Claim 42 words
The amplifier of claim 2 wherein said impedance responsive means comprises: automatic test means for automatically producing a signal corresponding to the impedance of said load; and means for producing said second control signal responsive to said automatic test means produced signal
Claim 6
Dependent Claim 102 words
The amplifier of claim 2 wherein said impedance responsive means comprises: selector means for manually entering one of: i) an input corresponding to the impedance of a load, or ii) an input commanding an automatic test of the impedance of said load; automatic test means responsive to an input commanding an automatic test of the impedance of said load for producing a signal corresponding to the impedance thereof; and means for producing said second control signal responsive to the selector means selected one of i) the input corresponding to the impedance of the load, or ii) the automatic test means produced signal.
Claim 7
Dependent Claim 38 words
The amplifier of claim 1 wherein said impedance responsive means comprises: means for manually entering an input corresponding to the impedance of said load; and means for producing said second control signal responsive to said manually entered input.
Claim 8
Dependent Claim 28 words
The amplifier of claim 6 further comprising: power supply means for predeterminedly varying the voltage bias on the amplifier's output devices in response to said second control signal.
Claim 9
Dependent Claim 42 words
The amplifier of claim 1 wherein said impedance responsive means comprises: automatic test means for automatically producing a signal corresponding to the impedance of said load; and means for producing said second control signal responsive to said automatic test means produced signal.
Claim 10
Dependent Claim 51 words
The amplifier of claim 8 wherein said automatic test means comprises: a signal generator for producing a predetermined test signal; means for coupling said test signal to said load; and measuring means for measuring the response of said load to said test signal and producing said second control signal responsive thereto.
Claim 11
Dependent Claim 70 words
The amplifier of claim 9 wherein: said signal generator produces a frequency swept, substantially constant current test signal; and said measuring means comprises: detector means for producing a signal corresponding to the value of the voltage developed across the load as a result of the test signal, integrator means for integrating the detector means produced signal, and processing means for processing said integrator means signal into said second control signal.
Claim 12
Dependent Claim 51 words
The amplifier of claim 10 wherein said processing means comprises: comparator means for comparing said integrator means signal with a set of predetermined reference levels, each reference level corresponding to a predetermined impedance, and logic means for producing said second control signal responsive to the result of said comparator means comparisons.
Claim 13
Dependent Claim 33 words
The amplifier of claim 9 wherein: said signal generator produces a frequency swept signal; and said measuring means comprises integrating means for integrating the response of said load to said frequency swept signal.
Claim 14
Dependent Claim 28 words
The amplifier of claim 8 further comprising: power supply means for predeterminedly varying the voltage bias on the amplifier's output devices in response to said second control signal.
Claim 15
Dependent Claim 102 words
The amplifier of claim 1 wherein said impedance responsive means comprises: selector means for manually entering one of: i) an input corresponding to the impedance of a load, or ii) an input commanding an automatic test of the impedance of said load; automatic test means responsive to an input commanding an automatic test of the impedance of said load for producing a signal corresponding to the impedance thereof; and means for producing said second control signal responsive to the selector means selected one of: i) the input corresponding to the impedance of the load, or ii) the automatic test means produced signal.
Claim 16
Dependent Claim 51 words
The amplifier of claim 14 wherein said automatic test means comprises: a signal generator for producing a predetermined test signal; means for coupling said test signal to said load; and measuring means for measuring the response of said load to said test signal and producing said second control signal responsive thereto.
Claim 17
Dependent Claim 33 words
The amplifier of claim 15 wherein: said signal generator produces a frequency swept signal; and said measuring means comprises integrating means for integrating the response of said load to said frequency swept signal.
Claim 18
Dependent Claim 70 words
The amplifier of claim 16 wherein: said signal generator produces a frequency swept, substantially constant current test signal; and said measuring means comprises: detector means for producing a signal corresponding to the value of the voltage developed across the load as a result of the test signal, integrator means for integrating the detector means produced signal, and processing means for processing said integrator means signal into said second control signal.
Claim 19
Dependent Claim 51 words
The amplifier of claim 17 wherein said processing means comprises: comparator means for comparing said integrator means signal with a set of predetermined reference levels, each reference level corresponding to a predetermined impedance, and logic means for producing said second control signal responsive to the result of said comparator means comparisons.
Claim 20
Dependent Claim 28 words
the amplifier of claim 14 further comprising: power supply means for predeterminedly varying the voltage bias on the amplifier's output devices in response to said second control signal.
Claim 21
Dependent Claim 27 words
The amplifier of claim 1 wherein said control means responds to said first and second control signals to bias said amplifier in substantially a class A mode.

References Cited (Backward Citations)

JPS5250654A Cited
US4077013A Cited
US4358739A Cited
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US4498057A Cited
US4549147A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-05-31 1996-11-30 1997-06-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-05-31 2000-11-30 2001-06-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-05-31 2004-11-30 2005-06-01 $7700.00 Window Closed / Lapsed

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