Resources Contact Us Home
Wireless frequency power amplifier, semiconductor device, and wireless frequency power amplification method

Image Number 16 for United States Patent #7683712.

A differential amplifier circuit is connected to the input node and the output node of the final amplification stage through detection circuits. The signal level difference output from the differential amplifier circuit does not change even if the input power varies. Because a change in the power gain at the output node does not travel back to the input node when the load impedance of the wireless frequency power amplifier varies, it is possible to detect only the change in the load impedance. Damage to the final stage can be prevented by controlling the operating current of the final stage and the gain of the drive stage according to the detected load variation. Nonlinear distortion in the wireless frequency power amplifier output can also be reduced by detecting and canceling the change in the gain of the drive stage by changing the gain of the adjustment stage.

  Recently Added Patents
Methods and systems for time-shifting content
Charged particle cancer therapy beam path control method and apparatus
Nitrogen-doped carbon-supported cobalt-iron oxygen reduction catalyst
Methods for the production of aligned carbon nanotubes and nanostructured material containing the same
Fabrication method of packaging substrate having through-holed interposer embedded therein
Methods and devices for coding and decoding images, computer program implementing them and information carrier enabling their implementation
  Randomly Featured Patents
Golf club head having a striking face with improved impact efficiency
Method and apparatus for molding multichamber squeeze tubes and tubes produced thereby
Microwave oscillator circuit with improved efficiency
Concealed playing piece apparatus
Styrene derivatives, their use as antiallergic agents and intemediate epoxides for their synthesis
Method for determining the position of a rotating shaft
Credit card reader
Method and apparatus for meta-shopping and dynamic setup of B2B ecommerce
Device for separating mixture
Method of fabricating vertically integrated oxygen-implanted polysilicon resistor