topic MKL17UART does not work at low temperatures in Kinetis Design Studio

MKL17UART does not work at low temperatures

gavinyork — Fri, 29 Jan 2016 03:15:44 GMT

MKL17 uart dont`t work at low temp and when at room temperature to work properly. Why?

Re: MKL17UART does not work at low temperatures

bobpaddock — Fri, 29 Jan 2016 13:35:48 GMT

What exactly is 'Low'?

What is the clock source as that is the most temperature dependent component?

Re: MKL17UART does not work at low temperatures

scottm — Sat, 30 Jul 2016 18:54:35 GMT

If you're running from the internal clock reference, check the frequency drift vs. temperature curve in the datasheet. Looks like it varies by maybe 0.5% over 20 degrees C, which could be enough to take your baud rate out of spec.

The one time I've gotten a crystal-referenced MCU enough out of spec to be a problem, I had it at about -190 C, just above the liquid level in a dewar of liquid nitrogen.

On the other hand, the first time I used Processor Expert for clock setup I accidentally selected the internal reference instead of external. My first prototype worked OK but without trimming it was hit or miss on the others.

Scott