STM32H735RGV6 and STM32H725RGV6 software compatibility?

[Ersin Kuscu]

We have a design based on STM32H735RGV6.

We are trying to move our design to STM32H725RGV6.

These two MCUs are pin compatible and can be used in the same design without changing the board design.

However, we are not sure about using the same software in these two MCUs.

Is there any limitation to using the same software for these two MCUs.

Note that: We are not using crypto/hash feature of STM32H735RGV6.

[Danish1]

As they share the same Reference Manual they should be fully compatible for everything that is present on both microcontrollers. But do compare the Data Sheets as well.

Your programmer might grumble if you haven't recompiled the code for the other part, and their device-IDs differ.

Problems might be encountered if you do not fully follow the instructions in the Reference Manual e.g. where bits of certain registers are labelled "Reserved, must be kept at reset value" and you write anything else there for convenience or through carelessness. But then those problems might also be seen if you try to use the same code on a different revision of the same chip.

My suspicion is that these devices are based on the same silicon die, but ST disable the crypto bits to allow them to sell it where they're not allowed to export such cryptography technology.

It's also possible that the crypto unit failed its production-tests on certain chips, and ST chose to sell them as parts without crypto rather than scrapping them entirely. (Many failures in chip production are due to a speck of dust landing at an unfortunate spot and knocking out a single transistor or connection; all other parts continue to work perfectly).

[KDJEM.1]

Hello @Ersin Kuşçu​,

If your project is based on a generation of code with STM32CubeMX, this article can help you to migrate your current example with STM32H735RGV6 to the STM32H725RGV6.

When your question is answered, please close this topic by choosing Select as Best. This will help other users find that answer faster.

Thank you.

Kaouthar