H7 series peripheral performance in VOS2 and 3

[MikeDB]

The datasheets for the interface characteristics of each peripheral state "VOS level set to VOS1" which is the 400MHz option. But no information is given on if any of the peripherals derate if you use the slower speed and power VOS options. Would especially be interested in whether the max speed of the SPI1-3 degrade from 100MHz. I'm suspecting they might as SPI4-6 are in a different power area and only run at 50MHz.

[TDK]

Look at "Table 55. Kernel clock distribution overview".

The SPI data rate can be half of the kernel clock rate (with a prescaler of 2), subject to the maximums in the table.

So SPI1,2,3 can be 100/100/75/50 Mbit/s max at VOS0/VOS1/VOS2/VOS3.

And SPI4,5,6 can be 62.5/50/37.5/25 Mbit/s max.

(Presumably the second "VOS2" column is a typo and should read "VOS3".)

[MikeDB]

Can you give me a link to the document you are referencing. In the one I am using Table 55 is about ESD and it sounds like the one you have is what I need.

[TDK]

RM0433

[MikeDB]

Hmm - RM0433 says max 100Mbps for VO1 as you say, but the datasheet says 133 MHz. I'll assume the slower of the two.

[TDK]

Seems safe. There are a few different H7 lines with different datasheets and reference manuals. It’s possible it varies. You didn't mention which chip you’re using so I just guessed

[MikeDB]

Sorry - H750. But I've always assumed the H7 devices are just the one design with different bits enabled and tested.

[Tesla DeLorean]

https://www.st.com/content/ccc/resource/technical/document/reference_manual/group0/c9/a3/76/fa/55/46/45/fa/DM00314099/files/DM00314099.pdf/jcr:content/translations/en.DM00314099.pdf