This is my first time making a PCB. I use an STM32F103C6T8 and I need an HSE (4 to 16 MHz).

I chose this one but I have two doubts:

  • Did I choose correctly?

  • It has only two pins (I imported it on Altium), but usually online I see configurations with four pins with pF capacitors. Do I plug the pins directly into OSC_IN and OSC_OUT?

From the datasheet I don't understand much beyond the limit values.

  • \$\begingroup\$ Your data sheet is common for a wide range of crystals. It's unknown what you chose and if it is suitable or correct. Please tell what exactly you chose \$\endgroup\$
    – Justme
    Nov 14, 2022 at 23:06

1 Answer 1


It's always a good idea to poke around the manufacturer's site to see if there are app notes or white papers for design problems and ST has an excellent guide for designing oscillator circuits:


There is additional implementation information and schematic on page 52/table 22/fig. 24 of the STM32 datasheet that shows you how to connect the crystal and the additional components required (two capacitors and a resistor).

Bare crystals can come in 2- and 4-pin packages (as well as other configurations). Section 7 of the linked app note has some excellent tips for layout to prevent undesirable performance. Or you could take a look at section 5.3.6 of the STM32 datasheet and use a complete monolithic oscillator.


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