Back to results
US 5,216,379 AGranted
Dynamic bias amplifier
OwnerJames P. Hamleyinventor
Life of this patent
Estimating the term…
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.
Claims20
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.
6 more elements
Dependencies are inferred from the claim text.