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jom sabu
Associate
January 12, 2018
Question

LM358: Circuit verification

  • January 12, 2018
  • 1 reply
  • 826 views
Posted on January 12, 2018 at 12:26

Hello Sir,

We have used opamp ic LM358 in our audio project, which used for amplification of signal from mic to adc of microcontroller.

Could you please verify the attached circuit, let me know if you have any comments.

Regards

Jom

    This topic has been closed for replies.

    1 reply

    Pierre SENNEQUIER
    ST Employee
    January 25, 2018
    Posted on January 25, 2018 at 10:54

    Hi Sir,

    The cutoff frequencies are too high for audio signal (10nF and 1kOhm => 15.9kHz and 1.5nF and 330 Ohm => 322kHz).

    If you want to keep the gain unchanged, you should increase the 10nF and 1.5nF capacitors to respectively at least 10uF and 22uF.

      Best Regards,

    P