PWM to analog for audio

Fabien Reversat

Prodigy 10 points

Hello,

What would you recommend for converting a PWM audio signal to an analog output ?

Here are some details:

PWM frequency = 40 kHz
PWM Duty Cycle depends on microphone voltage :
- Max Voltage >> Duty Cycle 100%
- 0 V >> Duty Cycle 50%
- Min voltage >> Duty Cycle 0%

Thanks,

Fabien

over 2 years ago

0 Ivan Salazar over 2 years ago

TI__Guru** 102545 points

Hi Fabien,

There are some amplifiers specifically for PWM input, although the frequency range may not match your application: https://www.ti.com/audio-ic/amplifiers/speaker-amplifiers/products.html#p2982=PWM

Alternatively I would suggest to use any analog input amplifier, and use a low-pass filter to make the PWM signal into an analog-like one. Second order filter may be a good option due to PWM frequency too close to the audio band.

Best regards,
-Ivan Salazar
Applications Engineer

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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PWM to analog for audio