2021-05-26 11:39 AM
Hello, the datasheet of STM32F030C8 say to use 100nF and 4,7uF capacitor. I have a doubt about the type of this 4,7uF capacitor. I have to use a ceramic, tantalum ou electrolytic? If I use a ceramic, this need a specific model or any ceramic capacitor?
And about the reset? Not is necessary a pull-up resistor? What that "(3)" in the capacitor?
2021-05-26 12:46 PM
The 4u7 is a bulk capacitor to supply instantaneous current as all the CMOS circuitry switches synchronously. Tants would probably be ideal, but ceramics would also be fine. Want something with relatively low ESR so the energy can be delivered quickly and efficiently.
3) is to slow the rise-time of the reset, and debounce the switch. The STM32 has an internal pull-up, doesn't preclude you from using one, or using a more effective POR circuit