PWM signal generation using Aurix TC399 with low tolerance

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Amr-khaled-Aziz
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Hello All,

I am working on a project where I need to accurately generate a PWM signal with a 50% duty signal with a 1 Hz frequency.

I tried using CCU6 interrupt, GTM (TOM/ATOM), GPT12, and FreeRTOS but all yielded about ~265 us skew per sec as measured by a logical analyzer and a pico-scope.

As per my understanding, the tolerance for the source crystal oscillator is 50 ppm which is equivalent to 50 us per sec, so I aim to stay within this error margin.

How can I achieve such a signal with the latter skew tolerance?

BR,

Amr Khaled

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David_R
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Hi @Amr-khaled-Aziz 

The full details of the electrical specifications and clock system as well can be found on MyICP platform

There you can find tables with all the osc_xtal, sys_pll, and per_pll parameters, simulation models for the TC39x family,  also there're some app notes that could be useful Crystal Oscillator Basics and Oscillator handling,

Regards! :1

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Amr-khaled-Aziz
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Hello @David_R ,

I am afraid after several trials the problem persists, also many of the resources are not accessible, can you tell me if this skew of about 180 us per second is expected in this scenario or if there is a solution for this?

BR

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David_R
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Hello @Amr-khaled-Aziz 

To be able to access the documents you'll need a MyICP account, if you already have one but can not access please let me know,

On the other hand can you please tell if it's a develepoment board from infineon or it's a custom one?, may i know what are you trying to achieve?, can you share you project to be able to help you more quickly?

Regards! :1

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Amr-khaled-Aziz
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Hello @David_R ,

Yes I am using the original Aurix TC399XP kit from Infineon, I am trying to generate an accurate PPS (pulse per second) for synchronization with Lidar but this signal is needed with high accuracy.

BR,

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Erick_G
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10 likes received 100 sign-ins 25 solutions authored

This thread follows the same question, please add any update there.

Please don't create several threads for the same issue.

Best regards,

Erick

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