i.MX RT1064 external CLK1 input usage

[_Chris_]

Hi,

At this moment I'm evaluating the i.MX RT1064 with the MIMXRT1064-EVK which is going well.
For future product development we are investigating the possibilities for this processor to clock some external peripherals with a clock derived from a source other than the 24MHz.

For this the i.MX RT1064 seems to provide an external CCM_CLK1_P/CCM_CLK_N input which can be selected by using the MCUXpresso IDE clock configurator.

However the design documentation is not clear about this function, the "i.MX RT Hardware Development Guide for the MIMXRT1050/MIMXRT1060 Processor (REV 4)" states in Table 4. on page 9:

While in the "i.MX RT1064 Crossover Processors Data Sheet for Consumer Products, Rev. 2, 08/2020" states in chapter 3.1 on page 16:

The question is, which of the table is correct, can this input be used for normal operation or not ? and if so has this any side effects which should be taken into account ?

Best Regards,

Chris

[jingpan]

Hi Chris,

I think you'd better leave these pins unconnected. In fact, in hardware development guide Rev.2 this two pins can be used to input clock. So, I think this is not a typo.

Regards,

Jing

[_Chris_]

Hi Jing,

I'm afraid my question wasn't clear, so let's rephrase my question.

The problem I have is I would like to use these pins as an external clock source as mentioned in the "i.MX RT1064 Crossover Processors Data Sheet for Consumer Products, Rev. 2, 08/2020".

However the "i.MX RT Hardware Development Guide for the MIMXRT1050/MIMXRT1060 Processor (REV 4)" states "it is for internal use only" "It is used only for internal test, please make CLK1_N/P pairs remain unconnected."

Which suggests I can't use them because they are for "internal use ony".

Are these pins supposed to be used for clocking in normal use,  or is it only used during "manufacturing of the chip / internal use by NXP" ?

Best Regards,

Chris

[jingpan · Accepted solution]

Hi Chris,

They are "manufacturing of the chip / internal use by NXP".

Regards,

Jing