The appropriate amount of current for FM4's external clock

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JuIn_1625121
Level 5
Level 5
100 sign-ins First solution authored 100 replies posted

FM4 Peripheral manual(002-04856 rev.E page.260) has Following description.

-The appropriate amount of current flowing to the amplifier circuit varies depending on the

characteristic (ESR) and load capacitance (CL) of the oscillator connected to the VBAT Domain.

Select an appropriate amount of current by performing a matching evaluation between the VBAT

Domain and the crystal oscillator.

I think that Selecting an appropriate amount of current is following method.

(1)At first,  Perform a matching in standard condition.

(2)Only when the matching is not successful,  change the value of the register to change the current, and choose one for good results.

Is this way correct?

If No, please tell another method.

Best Regards,

Inoue

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1 Solution
Takashi_M
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1000 replies posted 500 solutions authored 750 replies posted

Regarding the matching test, it would be better to contact crystal (oscillator) vendor.

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2 Replies
Takashi_M
Moderator
Moderator
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1000 replies posted 500 solutions authored 750 replies posted

Regarding the matching test, it would be better to contact crystal (oscillator) vendor.

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Okay, I'll leave it to the Crystal vender.

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