AM3352: Regarding interrupt specifications and internal clock multiplication

Hello Sakai

Thank you for the query.

Ryosuke Sakai said:

Is there a block that internally multiplies the clock from OSC0_IN?

In EMC, there are many spectrums that are multiplied by 25MHz input from OSC0_IN, and I am looking for any part of the multiplication within AM3352.

I need more details. 

There will be PLLs that will use the OSC0_in and generate different frequencies.

For the timing, please refer the below section of the data sheet 

7 Peripheral Information and Timings

We have an FAQ that lists the links to key collaterals that you could refer

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1189177/faq-am3351-am3352-am3354-am3356-am3357-am3358-am3359-custom-board-design-collaterals-to-get-started

Regards

Sreenivasa

Hello Sreenivasa

Thank you for your responce.

In EMC, a frequency component that is 7 times OSC0_IN (25MHz) is detected. Does clocking OSC0_IN 7x work?

One of the two questions I asked has not been answered. Please also respond.

Is it okay to consider Interface clock to be equivalent to OSC0_IN (CLK_M_OSC, XTALIN)?

The technical manual states that the minimum pulse width on the input GPIO to trigger a synchronous interrupt request is two times the internally gated interface clock period.

Best regards,

R.Sakai

Hello Sakai

Thank you.

Ryosuke Sakai said:

In EMC, a frequency component that is 7 times OSC0_IN (25MHz) is detected.

Do you have the Ethernet interface or any other peripheral working at 25M?

Ryosuke Sakai said:

Is it okay to consider Interface clock to be equivalent to OSC0_IN (CLK_M_OSC, XTALIN)?

Did you have a chance to look at the clock tree tool

CLOCKTREETOOL-SITARA — Clock Tree Tool for AM335x, AM437x, AM437xHs, AM438x, AM57x, AM65x

https://www.ti.com/tool/CLOCKTREETOOL

Regards,

Sreenivasa

Hello Sakai

Thank you.

Ryosuke Sakai said:

In EMC, a frequency component that is 7 times OSC0_IN (25MHz) is detected.

Do you have the Ethernet interface or any other peripheral working at 25M?

Ryosuke Sakai said:

Is it okay to consider Interface clock to be equivalent to OSC0_IN (CLK_M_OSC, XTALIN)?

Did you have a chance to look at the clock tree tool

CLOCKTREETOOL-SITARA — Clock Tree Tool for AM335x, AM437x, AM437xHs, AM438x, AM57x, AM65x

https://www.ti.com/tool/CLOCKTREETOOL

Regards,

Sreenivasa

Hello Sakai

Please refer below section of the TRM.

Regards,

Sreenivasa

Hello Sreenivasa

Thank you for your responce.

Regarding the interface clock, I solved it with Clock Tree Tool.

Do you have the Ethernet interface or any other peripheral working at 25M?

=>There are no peripherals running at 25MHz. I am not using Ethernet, but I am using a BLE module (CC2650MODA).

Best regards,

R.Sakai

Hello Sakai

Thank you.

Do you see any thoughts on the BLE device being the source of EMC.

regards,

Sreenivasa

Hello Sreenivasa

Thank you for your responce.

I’m not sure. So I'm looking into things that seem to be related.
As far as I can see from the datasheet, 25MHz is not used in the BLE Module (CC2650MODA), so I think that AM3352, which has 25MHz input, is more suspicious.

Best regards,

R.Sakai

Hello Sakai

Thank you.

With the provided information not sure if i have any additional thoughts or inputs.

Could you please  confirm you have taken care of the below.

https://www.ti.com/lit/er/sprz360i/sprz360i.pdf

Regards,

Sreenivasa