Class D Amplifier Output Power Measurement

[contagiouseddie]

class d measurement

I'm developing a circuit using a class D amplifier from Maxim. The output of this amplifier is in Pulse Width Modulation (PWM) form. I'm wondering how can we measured the output power from this amplifier knowing that it is in digital form.

Thank you in advance.

 

[EcraZ]

measure class d amplifier

The PWM output when drives a transducer, say will have the average current for each pulse flowing in the device so maybe you can use a lowpass filter to get the original waveform and then use the appropriate formula/method to get the power.

Correct me if iam wrong.

 

[contagiouseddie]

class d amplifier power measurements

There's 4 channel output from the amplifier (Left+, Left-, Right+, Right-).Should I low pass filter 2 channel or 1 channel at a time is adequate?

 

[EcraZ]

measure class d amp

I guess it is two channel with Left and Right Outputs the + and - indicating polarity of the output. You can measure from one channel , tha tshout do

 

[skal81]

d-amp power measurement

I think you should use the AudioPrecision audio analyzer. You'll find more information at https://www.audioprecision.com/index.php. There are also some tutorials about measurements, including class D amp.
You can also refer to the following document by TI. By the way TI, ADI seems to be using the AudioPrecision analyzer (from the documents, article...)
Hope it helps

 

[dasong]

power measurement for class a amplifier

What is Class D Amplifier?what is the difference between Class A ,Class B or Class AB?