Abstract: A self-oscillating switching amplifier having an error amplifier output combined with the output of an output signal differentiator according predetermined weighing factors to force a small oscillation around the averaged output signal at a high frequency. The feedback voltage is sensed at the output of the switching amplifier. Additional feedback can be derived from a switching node of the power switch. The switching of the power switch can be dynamically changed from binary switching when the amplitude of the audio signal is low, to ternary switching when the amplitude of the input signal is high to minimize distortion of the output signal. The amplifier can be supplied with a pulsing voltage. In certain embodiments the output signal differentiator is simply a capacitor or a LC resonance circuit coupled directly to an appropriate speaker terminal for the highest possible self-oscillating frequency of the switching amplifier.

Abstract: Effective bandwidth of a communication link is determined in a heterogeneous, packet switched network between a source and a destination, where effective bandwidth is defined as the actual available bandwidth between the server and the client, minus the overhead of the various network protocols used to transmit the data. The method includes maintaining a database of bandwidth parameters indexed by destination address, and using the database when setting a communication channel.