Choosing 24MHz Crystal Oscillator for i.MX7

[ko-hey]

Hi all

Let me confirm about the 24MHz Crystal Oscillator requirement for i.MX7.

I try to find some requirement in datasheet and reference manual but I can't.

On the other hand, some recommendations for other i.MX series are available in community etc,.

What data we need is "center frequency" , "Tolerance", "CL", "ESR" and "Max drive level".

Could you answer me whether those recommendation ca apply for i.MX7 or not ?

Please check following question.

1. For center frequency,

I found a following description in Section 4.8 XTAL Electrical Specifications of IMX53CEC. 

Can it apply for i.MX7 ?

2.For Tolerance

I found a folllowing description in section 2.5. Oscillator tolerance of http://www.nxp.com/assets/documents/data/en/user-guides/IMX7DSHDG.pdf.

which tolerance value is your recommendation if user don't use above three interface ?

3. For CL & ESR:

I found following thread.

https://community.nxp.com/message/337037

Can it apply for i.MX7 ?

4. For Max drive level

I found following description in table 1 of http://cache.nxp.com/assets/documents/data/en/engineering-bulletins/EB830.pdf?

Can it apply for i.MX7 ?

Ko-hey

[Yuri · Accepted solution]

Hello,

 IMX7 Design Checklist does not mention about specific requirements

for 24 MHz XTAL ; generally, for assurance, You may follow i.MX6 ones,

which are more strict.

“Connect a fundamental-mode crystal between XTALI and XTALO. An 80 Ω typical

ESR crystal rated for a maximum drive level of 250 μW is acceptable.

Alternately, a 50 Ω typical ESR crystal rated for a maximum drive level of 200 μW

may be used. See the engineering bulletin EB830 for additional options”.

If Your applications do not provide any (real) timing requirements - there are no formal restrictions

for crystal stability. Nevertheless, the list of crystal parts, mentioned in 24 MHz Crystal Specifications ? 
may be recommended.

Parameters of section 4.8 XTAL Electrical Specifications of IMX53CEC may be applied for i.MX7.

Regards,

Yuri.