Looking for MCU having 2× MDIO interfaces,3× I2C bus interfaces

Ganapriya · ‎2026-02-16

I am currently evaluating microcontroller options for our project and need your support in identifying a suitable MCU.
Our key interface requirements are as follows:

2× MDIO interfaces,3× I2C bus interfaces

If you could recommend an MCU that supports these features or share any relevant technical details/datasheets, it would be very helpful.
If not, please also suggest alternate part numbers that can meet this requirement.

mƎALLEm · ‎2026-02-18

That depends also on the RAM%/Flash size/Max frequency to optimize the price.

For 64/100 pins and using CubeMx tool, these are the part numbers proposed for only LQFP64 and LQFP100 with their corresponding unit price for 10kU:

You need to fine tune your choice by reading the product datasheet based on the flash size and the memory size and your application needs.

For example for the case of STM32H742 (DS12110), the internal memory sizes (Flash and SRAM) change according to the part number:

.

All the part numbers listed in this datasheet have one MDIO slave instance:

And four I2C instances:

The ordering information chapter gives more information about the part number:

Hope that I've answered your question.

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View solution in original post

mƎALLEm · ‎2026-02-16

Hello @Ganapriya and welcome to the ST community,

You can use MCU finder downloadable from this link. Or CubeMx downladable from here to find tune your finding.

Meanwhile, to my knowledge no STM32 microcontroller currently offers two native MDIO interfaces. Only one MDIO (slave only) is available for example on STM32H7 and 4xI2C are available.

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Ganapriya · ‎2026-02-18

Hi,

We need MCU which has pins of 64 and 100 pins and supports I2C on STM32H7. Can you suggest the extract part number from this series?

mƎALLEm · ‎2026-02-18

That depends also on the RAM%/Flash size/Max frequency to optimize the price.

For 64/100 pins and using CubeMx tool, these are the part numbers proposed for only LQFP64 and LQFP100 with their corresponding unit price for 10kU:

You need to fine tune your choice by reading the product datasheet based on the flash size and the memory size and your application needs.

For example for the case of STM32H742 (DS12110), the internal memory sizes (Flash and SRAM) change according to the part number:

.

All the part numbers listed in this datasheet have one MDIO slave instance:

And four I2C instances:

The ordering information chapter gives more information about the part number:

Hope that I've answered your question.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

Andrew Neil · ‎2026-02-18

@Ganapriya wrote:
We need MCU which has pins of 64 and 100 pins and supports I2C on STM32H7.

I don't think there would be any STM32 which didn't have at least one I2C !

@Ganapriya wrote:
Can you suggest the extract part number

No - because, as @mƎALLEm said, we don't know your complete requirements.

Here are some product selectors where you can enter all your requirements:

STM32 MCU product selector

STM32 product finder for mobile devices

STM32 and STM8 product finder for desktops

and, as @mƎALLEm said, you can also use CubeMX

Distributors also often have parametric search facilities ...

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

Ganapriya · ‎2026-02-27

Hi,

Suggest me MCU which has MDC/ MDIO, I2C and 64 pins Package.

Andrew Neil · ‎2026-02-27

Have you actually used any of the suggested search tools ?

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

mƎALLEm · ‎2026-02-27

It was already suggested in my previous post. There are many part numbers you can use, but that depends on your needs:

Did you use the CubeMx tool to fine tune your finding?

It's up to you to find the exact part number based on your needs (Flash size/price etc..)

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.