External Crystal Connection

[2013ee139]

Posted on June 27, 2016 at 19:40

Hello I am developing a evaluation board for STM32F427. I am connecting an external **RTC** IC (DS3231). Do i need to connect an other external oscillator for processor? Because in STM32F407 discovery board they have connected an external 8MHz crystal other than 32.768KHz which is used for **RTC**.

0

http://stackoverflow.com/questions/38059939/external-crystal-connection♯

Hello I am developing a evaluation board for STM32F427. I am connecting an external RTC IC (DS3231). Do i need to connect an other external oscillator for processor? Because in STM32F407 discovery board they have connected an external 8MHz crystal other than 32.768KHz which is used for RTC.

0

http://stackoverflow.com/questions/38059939/external-crystal-connection♯

Hello I am developing a evaluation board for STM32F427. I am connecting an external RTC IC (DS3231). Do i need to connect an other external oscillator for processor? Because in STM32F407 discovery board they have connected an external 8MHz crystal other than 32.768KHz which is used for RTC.

0

http://stackoverflow.com/questions/38059939/external-crystal-connection♯

Hello I am developing a evaluation board for STM32F427. I am connecting an external RTC IC (DS3231). Do i need to connect an other external oscillator for processor? Because in STM32F407 discovery board they have connected an external 8MHz crystal other than 32.768KHz which is used for RTC.

0

http://stackoverflow.com/questions/38059939/external-crystal-connection♯

Hello I am developing a evaluation board for STM32F427.

#!stm32-!clock #smt32f427

[Tesla DeLorean]

Posted on June 27, 2016 at 19:49

I'm not sure what the question is. How close is your design to that of the STM32F4-DISCO?

The F4 really needs an external HSE (High Speed, ie 4-26 MHz) source for USB and CAN to function within specifications.A LSE source is needed for the F4 to come out of STANDBY via the internal RTC, you could presumably supply that as a single pin clock source if you don't want a second crystal for that.