Patent ID: 6320460
Filing Date: 2001-11-20
Classification: H03F

Abstract:
A Class D amplifier, comprising:a) a source of split DC voltage having a Negative Voltage Rail, a Positive Voltage Rail and a Ground;b) an audio signal source connected to a First Input Resistor which is connected to the negative input of an Integrator;c) a Comparator, having a well-defined Hysterisis, with its input connected to said Integrator's output;d) a First Level Shifter comprising a First and a Second Capacitor connected in series between the output of said Comparator and the negative voltage rail so as to change the Ground Referenced Output Signal of said Comparator to said Negative Voltage Rail Referenced signal;e) said Negative Voltage Rail Referenced Signal at the junction of said First and Second Capacitor is connected to a First Buffer, andf) a Second Level Shifter utilizing a Transistor in a switched current source configuration wherein the signal derived from the collector of said transistor is floating and referenced to the output and is also in phase with the output signal achieving high .DELTA.v/.DELTA.t immunity;g) a First and a Second Asymmetrical Delay Network introducing the appropriate amount of delay in order to avoid simultaneous conduction;h) a Second Buffer driven by the collector of said Transistor having low output impedance in order to drive said Second Asymmetrical Delay Network;i) a First and a Second Output Switch driven by First and Second Driver stages that deliver high speed, high current pulses having input signals processed as described, and the junction of said First and Second Switches is capable of driving a low impedance load such as a loudspeaker; andj) a First Feedback Resistor is also connected between the negative input of said Integrator, and the said Output reducing non-linearities and distortion. The average value of the signal obtained at said Output will be defined as the value of said First Feedback Resistor divided by the value of the First Input Resistor times the Audio Input Signal.