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ADSP21565 Crystal design problems

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Product Number: ADSP21565
Software Version: NONE

Question 1: if the sys of DSP slave_ Clkin0 uses external crystal instead of sys of DSP master_ Clkout, is there a problem that two DSPs are not synchronized?

Question 2: after the customer connected the pin10 of the DSP master to the DSP slave pin5, the test found that the levels of pin10 and pin5 were not consistent, so it was poured back to VDD_ ANA and VDD_ CLK。 Cause VDD_ ANA and VDD_ The voltage of CLK rises from 1.8V to 2.0V. Is the pin10 of the DSP master unable to connect to the DSP slave pin5?

  • Hi,

    We understand that both DSP are ADSP-21565. Please refer our below reply:


    1. Yes, you can use external crystal for DSP subordinate. Also, what you mean by synchronization problem of two DSPs.


    2.  Power domain of SYS_CLKIN0 is VDD_REF and for SYS_CLKOUT is VDD_EXT. Both VDD_REF and VDD_EXT have different voltage levels. So, you cannot connect SYS_CLKOUT of main DSP to SYS_CLKIN0 of subordinate DSP.

    Regards,
    Anand Selvaraj.