Problem with high speed in a custom board with STM32H735IGT6

[JVale.2]

Hi.

I am Jose Manuel. We have developed a custom board where the MCU is STM32H735IGT6, the external SRAM is APS12808L-3OBMX-BA and the external flash is W25Q128JVEIM.

The problem is that we want to work with 100 MHz, but it does not work, it just work up to 60 MHz.

We have developed a board with four levels, the same lenghts in the route and the same vias. Below, attached the interface between the SRAM and MCU. Could you please tell us what steps we have not done? Whats the recommendation to follow?

Thanks you and Best regards,

José Manuel

[Alex - APMemory]

Is you issue about Flash or RAM?

Alex

[Tesla DeLorean]

Good question, but the word "RAM" with respect to the interface and the problem is used multiple times.

[JVale.2]

Hi everyone,

We have redesigned the board trying to set the impedance of the lines to 50 ohms and followed the steps in document AN4661 (section 8.4.3). The result has improved, we can work up to 120 MHz.

Thanks for your helps.

José Manuel

[Alex - APMemory]

Thanks for the confirmation and good to hear

Alex