US 12,445,096 B2
Output capacitance distortion correction for audio amplifiers
Mark R. Peting, Yamhill, OR (US); and Deepika Kumari, Portland, OR (US)
Assigned to Skyworks Solutions, Inc., Irvine, CA (US)
Filed by SKYWORKS SOLUTIONS, INC., Irvine, CA (US)
Filed on Sep. 28, 2022, as Appl. No. 17/955,107.
Claims priority of provisional application 63/250,169, filed on Sep. 29, 2021.
Prior Publication US 2023/0099719 A1, Mar. 30, 2023
Int. Cl. H03F 3/217 (2006.01); H04R 1/10 (2006.01); H04R 3/04 (2006.01)
CPC H03F 3/217 (2013.01) [H04R 1/1041 (2013.01); H04R 3/04 (2013.01); H03F 2200/03 (2013.01); H04R 2201/028 (2013.01); H04R 2420/07 (2013.01); H04R 2430/01 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An audio amplification system comprising:
a digital audio path configured to receive and process a digital signal, the digital audio path including a signal limiter and a digital-to-analog converter modulator;
an audio amplifier configured to receive the digital signal and provide an output signal to an output node for driving a load coupled to the output node that includes first and second pins connectable to the load, the output signal representative of the digital signal, the audio amplifier including an H-bridge driver configured to operate in a high-output resistance (HOR) mode or a zero-output resistance (ZOR) mode, the H-bridge driver including a first driver having an output coupled to the first pin through a sense resistance, a second driver having an output coupled to the first pin without a resistance, and a common driver coupled to the second pin, such that the first driver and the common driver are enabled for the HOR mode and the second driver and the common driver are enabled for the ZOR mode;
a controller configured to determine an amount of charge diverted away from the load due to a parasitic effect of the audio amplifier, the amount of charge including charge diverted away from the first pin when in the HOR mode such that the parasitic effect of the audio amplifier includes a parasitic capacitance associated with the second driver in a disabled mode; and
a correction block implemented between the signal limiter and the digital-to-analog converter modulator to be along the digital audio path and configured to provide an adjustment to the digital signal to compensate for the amount of charge diverted away from the load.