ADuCM360 AVDD

Hello

Our customer is designing his board using ADuCM360.

He looks that AVDD is connected to outptu of ADP1720 through  some capacitor and a bead in the description of the datasheet P.23 and UG-367 P.174 .

Do we need some capacitor and a bead  to meet the datasheet specification ?

Our customer would like to remove these capactior and a bead baceuse he would like to  design small board

If  there is any problem when we use normally LDO and 0.1uF only for AVDD connection,

Could you give me your advice ?

Regards,

Terumasa

  • The bead is there to prevent noise from the digital circuitry entering the sensitive analog circuitry.

     The bead is there to achieve best performance for the ADuCM360.

    Without it yes the performance can degrade but only you can figure out if this is a problem in your system or not.

    The performance degradation will be dependent on many factors including layout and system level noise.

    The ADI recommendation is to use the components for filtering and decoupling as recommended in the DS and in the evaluation board to achieve the DS specifications.