Hello, I'm an electronic engineer and I'm working on a project for automation of agricultural machinery, we are using in this project the microcontroller STM32F446RCT7TR.

[CSele.1]

Hello, I'm an electronic engineer and I'm working on a project for automation of agricultural machinery, we are using in this project the microcontroller STM32F446RCT7TR. however I have little experience in this microcontroller and so I'm sorry if my question is a little obvious.

My question is, we are using an 8 MHz oscillator crystal with a large package in the prototype, but for the product I need to use an SMD crystal with the smallest possible package, which one would you recommend?

And because the application note AN2867 - Table 7 only indicates crystals of 32.7 MHz

Thanks

[Tesla DeLorean]

You mean 32.768 KHZ, it focuses on those due to the lower power requirements and efficiencies, and a desire for them to start and oscillator properly.

The HSE drive pins are more aggressive.

If you want to lift some HSE examples, perhaps pull the current NUCLEO-144 and DISCO schematics and BOMs, where ST calls out specific makes and models. Watch the capacitors and topology.

Smallest possible? 3.2 mm x 2.5 mm? 2.5 mm x 2.0 mm ?

What can your PCB and PCBA work with? Determine what they are comfortable working with, and the costs.

 

[Tesla DeLorean]

https://www.st.com/resource/en/bill_of_materials/nucleo_144pins_bom.zip

Oscillator,NX3225GD-8MHz-EXS00A-CG04874,8MHz,8pF,SMT (3.2 x 2.5 mm)

https://www.digikey.com/en/products/detail/ndk-america-inc/NX3225GD-8MHZ-EXS00A-CG04874/9172047

[TDK]

If you can get by with +/-1% accuracy, you don't need an HSE at all and can use the internal HSI as a clock.