Suggest a smaller STM32 IC for BMS application

[VinceTai]

Dear Sir/Madam,

Good day~

I am trying to build a custom PCB with an STM32 chip.

Currently, NUCLEO-F439ZI Demo Board is used, but only few pins/functions of the STM32F439ZI chip are necessary for me, the used pins shown as below (20 out of 114 pins are utilized):

Then, I started to search appropriate chip by STM32 CubeMX, but the search list included more than 300 parts.

Therefore, is it possible for you to provide suggestions for an alternative STM32 MCU that has the following features:

1. 1x CANBUS Interface
2. 1x SPI interface
3. 1x Ethernet

Secondly, I would like to have the same debugging capabilities as the Nucleo boards which embed an ST-LINK. Hence, I would like to know more about the chip STM32F103CB which seems to be the one used to manage the ST-LINK on NUCLEO boards..

May I confirm that if I purchase several STM32F103CB chips, in order to use them for ST-LINK purpose.

Should I write program and flash it on each chip? Or each chip will be flashed in manufacture?

I will be grateful for any help and suggestion, thanks. 

Vince

[Peter BENSCH · Accepted solution]

Welcome @VinceTai, to the community!

A note in advance: the NUCLEO boards have an integrated ST-Link so that you can start programming and debugging straight away. Usually, however, the STM32 are used on your own board without ST-Link. If you really want to have an embedded ST-Link, the only way is to use a ready-made module STLINK-V3MODS, because the ST-Link firmware is not open source and is not available for download.

To your questions:

You have actually already taken the right path to selecting the right MCU. However, if you set the filters according to your requirements, you will not find a package smaller than 64pins, as an Ethernet MAC, a CAN MAC and the necessary flash require quite a lot of chip area, which is why a smaller package is not sensible. If the 64pin or 68pin packages come into question, you could take a look:

• STM32F107RBT6 (LQFP64)
• STM32F107RCT6 (LQFP64)
• STM32H563RGT6 (LQFP64), STM32H563RGV6 (VFQFPN68)
• STM32H563RIT6 (LQFP64), STM32H563RIV6 (VFQFPN68)
• STM32H7R3R8V6 (VFQFPN68)

Hope that helps?

Regards
/Peter

[VinceTai]

Dear Peter,

Thank you for prompt reply, which is very clear and helpful to me.

I will check the chip list you provided, and verify whether they can be utilized in my project.

If they were not sutiable, "STM32F439ZI" would still be utilized, thanks for mentioning me selecting the right one.

Furthermore, thanks for explaining the information related ST-Link; it is now clear to me.

Have a nice day~

Yours Sincerely,

Vince

[Andrew Neil]

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@Peter BENSCH wrote:

Usually, however, the STM32 are used on your own board without ST-Link.

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Absolutely.

@VinceTai but note that the ST-Link on your Nucleo board can be used to program & debug your custom board.

Details are in the Nucleo board's User Manual.