About Spread Spectrum of PLL2 for DDR3L with i.MX6UL

[yuuki]

Dear all,

We have a question about Spread Spectrum of PLL2 of i.MX6UL.

Only PLL2(SystemPLL) supports Spread Spectrum.

We want to use this Spread Spectrum for a peripheral.

However, this PLL2 is used for MMDC module.

When DDR3L is used, may this Spread Spectrum cause any trouble?

In this case should PLL4 be chosen for MMDC?

May I have advice?

Best Regards,

Yuuki

[art · Accepted solution]

Please refer to the following community thread:

https://community.nxp.com/message/376642

It says that the DDR3 memories working at 528MHz can tolerate the spread spectrum operation with frequency deviation range of 5 - 6 MHz and frequency modulation rate of 20 - 60 kHz.

Have a great day,
Artur

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[yuuki]

Dear all,

We want to apply Spread Spectrum for DDR3L to suppress the noise.

However, we must use PLL4 if Spread Spectrum adversely affects DDR3L.

May I have advice?

Best Regards,

Yuuki