i.MX6 Dual: Is the 2.2M resistor on 24MHz oscillator ***really*** needed?

[mlees]

Hi,

Please can you let me know if the 2.2M resistor recommended for 24MHz oscillator is always needed for i.MX6 dual / quad?     The reason for asking is that many automotive customers do not allow resistor values > 100K without additional testing.   Removing this resistor reduces the test cost for automotive customers significantly.

In ERR005777, it mentions that projected impact is a 1.5ms increase in start-up time.   We can tolerate this increase in order to remove the resistor.   Please can you confirm if this is the only effect, and also whether this errata is fixed for i.MX6 dual / quad plus?   Many thanks!

[markwilliams]

Sorry to dig this up but I have exactly the same question. There was never any reply to the above.

Adding 1.5ms to startup isn't a problem for our design. But I am wondering if there are any other undocumented side effects to omitting this resistor.

Mark

[Yuri]

Hello,

  The Hardware Guide recommends to bias XTALI with a 2.2 MOhm resistor to GND

in order to ensure reasonable start-up time. But some customers found that not using

the 2.2 MOhm resistor caused some of their systems not to start at all.

  So, this is actually required to get a safe and stable startup.

Have a great day,
Yuri

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