maximum frequency of STM32F0 @2,5v

[all]

Posted on February 29, 2016 at 15:57

Hi, 

What is the maximum frequency of STM32F030F4P6 at 2,5V ?

Does the supply voltage have an impact on choice of capacitor value ?

I'm planning to use 20pf capacitors and 8 mhz crystal 

On the STM32F0 discovery schematics, there is R22 resistor connected to the crystal with a value of 390ohm. Is it required ?

Thanks

#stm32f030f4p6

[Tesla DeLorean]

Posted on February 29, 2016 at 17:31

The capacitor and resistor values would depend on the characteristics of your chosen crystal. I would check the manufacturer's specifications, and part numbering schemes, to get a starting point there. There maximum frequency of the STM32F0 is going to be dependent on the speed of the transistors due to the CMOS process window, voltage, temperature and critical paths in the design. The flash array is likely to be a big contributor here, as it is large and slow. The 32-bit timers in the peripheral realm.

What does the data sheet indicate? There is usually a table of voltage, speed, and flash wait states. Look also at the L0 parts, these are apt to be viable at lower voltages.

The use of USB is also predicated on sufficient voltages for the pin drivers to meet specifications.

[all]

Posted on March 01, 2016 at 12:40

Hi,

Thanks for your reply

There is no indication of other maximum operating frequency when running at lower voltage than 3V3

The datasheet only indicate operating rate from 0-48mhz and voltage 2,4-4,0 an

mcu consumption @ 3v3 

[Self.Glenn]

Posted on March 01, 2016 at 21:14

Hi,

Page 74 of document titled:

STM32F051x4 STM32F051x6 STM32F051x8

Lists maximum frequency <2.7V @20MHz

>= 2.7V is 30MHz

Glenn

[all]

Posted on March 02, 2016 at 01:00

Thanks in STM32F030 manual, there's not such limit

Anyway to be safe I will not go higher than 16 MHZ

[Amel NASRI]

Posted on March 02, 2016 at 15:31

Hi gfranck,

As general recommendation: besides to referring to the operating conditions stated in 

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00088500.pdf

, I suggest you have a look to the 

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00089834.pdf

 (Getting started with STM32F030xx hardware development). This later provides tips on how to set your hardware in order to use STM32F030x devices in adequate conditions.

-Mayla