Output 48MHz system clock on a GPIO pin other than MCO pin

[eigenroot]

Posted on January 03, 2016 at 21:20

I want to output the max 48MHz clock signal on STM32F030 to drive another subcircuit. The problem is the chip STM32030F4P6 (TSSOP-20 package) I prefer to use doesn't have the MCO pin (PA8). So I have 2 questions:

1. Can this 48MHz signal be produced on another GPIO pin other than MCO pin?  

2. I cannot find the limitations of using 48MHz signal (like load impedance, max driving current, etc.). Where can I find the information? 

#clock #stm32

[waclawek.jan]

Posted on January 03, 2016 at 22:50

> 1. Can this 48MHz signal be produced on another GPIO pin other than MCO pin?  

No.

> 2. I cannot find the limitations of using 48MHz signal (like load impedance, max driving current, etc.). Where can I find the information?

Datasheet, I/O port characteristics chapter.

JW

[Tesla DeLorean]

Posted on January 04, 2016 at 01:36

Use an external 48 MHz XO and buffer that into the STM32 and your other parts, it will save you a pin.

You could get 24 MHz out of a timer pin.