TPA3221: HEAD modulation output waveform

PYTsai

Part Number: TPA3221

My customer are using HEAD modulation. They use AP to measure the THD+N is 0.1%.

However when they use Scope to probe the output to ground waveform they saw a distortion waveform as below

When change to AD modulation, they distortion disappear.

May i know why HEAD modulation see such distorion waveform ? and is there any problem with this waveform?

+1 Jesse Ji over 1 year ago

it is normal.

for HEAD is a type of high efficiency AD modulation.

To achieve high efficiency, pwm duty cycle become very small so that the output may saw some distortion.

but the difference of 2 output should have no distortion.

below link may help you understanding the difference between HEAD and AD.

thanks.

jess

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