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Associate
March 27, 2026
Question

Spread Spectrum on STM32H5 series

  • March 27, 2026
  • 2 replies
  • 202 views

I would like to enable spread spectrum on the STM32H573RIT6.

We are currently running on 250Mhz and at that frequency we have big peak which is 15dB above the limit, that's why I would be able to enable the spread spectrum. 

I looked into the STM32H7 example, so I am already aware and able to modify the PLL realtime. Now my question is how do I connect the DMA of the STM32H5 properly to a timer and a buffer to load the PLL. And also a question I have, what are good values for the PLL. 

 

2 replies

mƎALLEm
Technical Moderator
March 30, 2026

Hello,

Related ressources to this subject (not specific to STM32H5 product):

AN4850 "STM32 MCUs spread-spectrum clock generation principles, properties and implementation"

The knowledge base article: STM32H7 series spread-spectrum clock generation (SSCG)

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Associate
March 30, 2026

Thanks mEALLEm, 

I will look into this. 

So basically there is not an example for the STM32H5?

I can use the examples of the STM32H7 ofcourse but the DMA of the STM32H5 is different then that of the STM32H7. 

I was a little strugling with the GPDMA going from memory to peripheral with a timer as trigger. 

I hope I will get it running. 

mƎALLEm
Technical Moderator
March 31, 2026

Hello,


@hippieZwolle wrote:

I was a little strugling with the GPDMA going from memory to peripheral with a timer as trigger. 

I hope I will get it running. 


Need to separate questions in this community. For this one please open a new thread in STM32 MCUs Embedded software forum board.

 

 

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