US 6,788,151 B2 · Variable output power supply

Abstract

A variable output power supply for use in a highly efficient linear amplification system includes an envelope detector having at least one input for receiving an input signal to be amplified. The envelope detector generates, as an output, a control signal that is representative of an envelope of the input signal. The variable output power supply further includes a controllable source that is coupled to the envelope detector. The controllable source generates an output voltage and/or current that is responsive to the control signal, such that the output of the variable output power supply dynamically changes as a function of the envelope of the input signal. When employed in a linear amplification system, the variable output power supply provides a supply voltage to a linear amplifier which can be dynamically varied in response to the envelope of the input signal so as to provide a substantially constant voltage supply headroom for the amplifier. In this manner, an efficiency and frequency response of the amplification system is improved, and a reduction in overall power dissipation of the amplification system can be achieved.

Claims16

Dependent claims

A variable output power supply, comprising:

an envelope detector for receiving an input signal and for generating a control signal representative of an envelope associated with the input signal;
and
a controllable source for generating an output that dynamically varies in response to at least the control signal and functionally corresponds with the envelope of the input signal;
wherein the controllable source comprises:
a multiple output power supply having a plurality of outputs, the multiple output power supply generating at least one of:
(i) a plurality of substantially constant output voltages, and (ii) a plurality of substantially constant output currents corresponding to the plurality of outputs;
a multiplexing circuit responsive to at least one output selection signal for selecting at least one of the plurality of outputs;
and
control circuitry having an input for receiving the control signal, the control circuitry generating the at least one output selection signal.

6 more elements

An amplification system, comprising:

a variable output power supply, the variable output power supply having:
an envelope detector having an input for receiving an input signal presented thereto, the envelope detector generating a control signal that is representative of an envelope associated with the input signal;
and
a controllable source operatively coupled to the envelope detector, the controllable
source generating an output that dynamically varies in response to at least the control signal, whereby the output of the controllable source is a function of the envelope of the input signal;
an amplifier having a predetermined gain associated therewith, the amplifier having at least one supply input operatively coupled to the variable output power supply for receiving the output from the variable output power supply, an input for receiving the input signal, and an output for generating an output signal;
and
linearization circuitry operatively coupled to the amplifier, the linearization circuitry being configured to substantially remove a nonlinear component in the output signal generated by the amplifier.

5 more elements

In a linear amplification system having an amplifier, a method of providing a variable output power supply, the method comprising the steps of:

detecting an envelope of an input signal to be amplified;
generating a control signal, the control signal being a function of the envelope of the input signal;
providing a controllable source, the controllable source having a plurality of outputs and being configured to generate at least one of:
(i) a plurality of output voltages, and (ii) a plurality of output currents corresponding to the outputs of the controllable source;
selecting at least one of the outputs generated by the controllable source in response to the control signal to generate an output supply signal of the variable output power supply, whereby the output supply signal is a function of the envelope of the input signal;
and
substantially removing at least a portion of a nonlinear component associated with an output signal generated by the amplifier.

4 more elements

Dependencies are inferred from the claim text.

Variable output power supply

Life of this patent

Variable output power supply

Life of this patent

Abstract

Claims16