Resources Contact Us Home
Power amplifier with controlled output power

Image Number 2 for United States Patent #7560989.

The invention includes a power amplifier with an amplifier core including parallel amplifier cells, a replica cell made of one amplifier cell similar to those of the amplifier core, a power controller to select a combination of amplifier cells to activate, a regulator to fix the top voltage of the replica cell to a reference voltage, a voltage generator to provide the voltage reference to the regulator, a current generator to provide a reference current through the replica cell, and a drive unit controlled by the regulator output to drive the combination of amplifier cells, so that each selected combination of activated cells defines a predetermined attenuation level of power amplifier output signal so that it is attenuated in a stepwise manner.

  Recently Added Patents
Firewall-tolerant voice-over-internet-protocol (VoIP) emulating SSL or HTTP sessions embedding voice data in cookies
Method and apparatus for information exchange over a web based environment
Device for installing conducting components in structures
Laboratory spatula
Cryptography on a simplified elliptical curve
Highly specialized application protocol for email and SMS and message notification handling and display
  Randomly Featured Patents
Power vent water heater with electronic control system
Caching process data of a slow network in a fast network environment
Sight glass assembly
Flux sensitive tracking
Fibrillated rayon-containing, water-decomposable fibrous sheet
Vane pump with flexible tongue valve
Frequency shifted laser transmitter
Collapsed gibbs sampler for sparse topic models and discrete matrix factorization
Method and apparatus for measuring the mass of a flowing medium
Method and apparatus for taking up tape