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RC4558: SNR parameter and package

Part Number: RC4558


1. Could you let me know the SNR parameter of RC4558? Or how to evaluate the SNR performance?

2. For the second SOIC (8), it should be VSSOP. Could help confirm?


  • Hi Dongbao,

    SNR is the difference between the output noise voltage and the full-scale output voltage. This difference is measured in dB. So you basically set an input signal to the amp that sets a full-scale signal at the output and set your dB reference to 0, then you AC-couple the inputs to GND in order to measure noise voltage and measure the difference with the reference in dB.
    This document gives some guidelines for several audio performance measurements:

    Yes, there is a typo in Device Information table, the second SOIC should be VSSOP-DGK.

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators